| Step | Hyp | Ref | Expression | 
						
							| 1 |  | seqf1o.1 |  |-  ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S ) | 
						
							| 2 |  | seqf1o.2 |  |-  ( ( ph /\ ( x e. C /\ y e. C ) ) -> ( x .+ y ) = ( y .+ x ) ) | 
						
							| 3 |  | seqf1o.3 |  |-  ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) ) | 
						
							| 4 |  | seqf1o.4 |  |-  ( ph -> N e. ( ZZ>= ` M ) ) | 
						
							| 5 |  | seqf1o.5 |  |-  ( ph -> C C_ S ) | 
						
							| 6 |  | seqf1olem.5 |  |-  ( ph -> F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 7 |  | seqf1olem.6 |  |-  ( ph -> G : ( M ... ( N + 1 ) ) --> C ) | 
						
							| 8 |  | seqf1olem.7 |  |-  J = ( k e. ( M ... N ) |-> ( F ` if ( k < K , k , ( k + 1 ) ) ) ) | 
						
							| 9 |  | seqf1olem.8 |  |-  K = ( `' F ` ( N + 1 ) ) | 
						
							| 10 |  | fvexd |  |-  ( ( ph /\ k e. ( M ... N ) ) -> ( F ` if ( k < K , k , ( k + 1 ) ) ) e. _V ) | 
						
							| 11 |  | fvex |  |-  ( `' F ` x ) e. _V | 
						
							| 12 |  | ovex |  |-  ( ( `' F ` x ) - 1 ) e. _V | 
						
							| 13 | 11 12 | ifex |  |-  if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) e. _V | 
						
							| 14 | 13 | a1i |  |-  ( ( ph /\ x e. ( M ... N ) ) -> if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) e. _V ) | 
						
							| 15 |  | iftrue |  |-  ( k < K -> if ( k < K , k , ( k + 1 ) ) = k ) | 
						
							| 16 | 15 | fveq2d |  |-  ( k < K -> ( F ` if ( k < K , k , ( k + 1 ) ) ) = ( F ` k ) ) | 
						
							| 17 | 16 | eqeq2d |  |-  ( k < K -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) <-> x = ( F ` k ) ) ) | 
						
							| 18 | 17 | adantl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ k < K ) -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) <-> x = ( F ` k ) ) ) | 
						
							| 19 |  | simprr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> x = ( F ` k ) ) | 
						
							| 20 |  | elfzelz |  |-  ( k e. ( M ... N ) -> k e. ZZ ) | 
						
							| 21 | 20 | zred |  |-  ( k e. ( M ... N ) -> k e. RR ) | 
						
							| 22 | 21 | ad2antlr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> k e. RR ) | 
						
							| 23 |  | simprl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> k < K ) | 
						
							| 24 | 22 23 | gtned |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> K =/= k ) | 
						
							| 25 |  | f1of |  |-  ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) -> F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 26 | 6 25 | syl |  |-  ( ph -> F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 27 | 26 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 28 |  | fzssp1 |  |-  ( M ... N ) C_ ( M ... ( N + 1 ) ) | 
						
							| 29 |  | simplr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> k e. ( M ... N ) ) | 
						
							| 30 | 28 29 | sselid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> k e. ( M ... ( N + 1 ) ) ) | 
						
							| 31 | 27 30 | ffvelcdmd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( F ` k ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 32 |  | elfzp1 |  |-  ( N e. ( ZZ>= ` M ) -> ( ( F ` k ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` k ) e. ( M ... N ) \/ ( F ` k ) = ( N + 1 ) ) ) ) | 
						
							| 33 | 4 32 | syl |  |-  ( ph -> ( ( F ` k ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` k ) e. ( M ... N ) \/ ( F ` k ) = ( N + 1 ) ) ) ) | 
						
							| 34 | 33 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( ( F ` k ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` k ) e. ( M ... N ) \/ ( F ` k ) = ( N + 1 ) ) ) ) | 
						
							| 35 | 31 34 | mpbid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( ( F ` k ) e. ( M ... N ) \/ ( F ` k ) = ( N + 1 ) ) ) | 
						
							| 36 | 35 | ord |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( -. ( F ` k ) e. ( M ... N ) -> ( F ` k ) = ( N + 1 ) ) ) | 
						
							| 37 | 6 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 38 |  | f1ocnvfv |  |-  ( ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) /\ k e. ( M ... ( N + 1 ) ) ) -> ( ( F ` k ) = ( N + 1 ) -> ( `' F ` ( N + 1 ) ) = k ) ) | 
						
							| 39 | 37 30 38 | syl2anc |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( ( F ` k ) = ( N + 1 ) -> ( `' F ` ( N + 1 ) ) = k ) ) | 
						
							| 40 | 9 | eqeq1i |  |-  ( K = k <-> ( `' F ` ( N + 1 ) ) = k ) | 
						
							| 41 | 39 40 | imbitrrdi |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( ( F ` k ) = ( N + 1 ) -> K = k ) ) | 
						
							| 42 | 36 41 | syld |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( -. ( F ` k ) e. ( M ... N ) -> K = k ) ) | 
						
							| 43 | 42 | necon1ad |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( K =/= k -> ( F ` k ) e. ( M ... N ) ) ) | 
						
							| 44 | 24 43 | mpd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( F ` k ) e. ( M ... N ) ) | 
						
							| 45 | 19 44 | eqeltrd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> x e. ( M ... N ) ) | 
						
							| 46 | 19 | eqcomd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( F ` k ) = x ) | 
						
							| 47 |  | f1ocnvfv |  |-  ( ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) /\ k e. ( M ... ( N + 1 ) ) ) -> ( ( F ` k ) = x -> ( `' F ` x ) = k ) ) | 
						
							| 48 | 37 30 47 | syl2anc |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( ( F ` k ) = x -> ( `' F ` x ) = k ) ) | 
						
							| 49 | 46 48 | mpd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( `' F ` x ) = k ) | 
						
							| 50 | 49 23 | eqbrtrd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( `' F ` x ) < K ) | 
						
							| 51 |  | iftrue |  |-  ( ( `' F ` x ) < K -> if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) = ( `' F ` x ) ) | 
						
							| 52 | 50 51 | syl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) = ( `' F ` x ) ) | 
						
							| 53 | 52 49 | eqtr2d |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 54 | 45 53 | jca |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( k < K /\ x = ( F ` k ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) | 
						
							| 55 | 54 | expr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ k < K ) -> ( x = ( F ` k ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 56 | 18 55 | sylbid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ k < K ) -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 57 |  | iffalse |  |-  ( -. k < K -> if ( k < K , k , ( k + 1 ) ) = ( k + 1 ) ) | 
						
							| 58 | 57 | fveq2d |  |-  ( -. k < K -> ( F ` if ( k < K , k , ( k + 1 ) ) ) = ( F ` ( k + 1 ) ) ) | 
						
							| 59 | 58 | eqeq2d |  |-  ( -. k < K -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) <-> x = ( F ` ( k + 1 ) ) ) ) | 
						
							| 60 | 59 | adantl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ -. k < K ) -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) <-> x = ( F ` ( k + 1 ) ) ) ) | 
						
							| 61 |  | simprr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> x = ( F ` ( k + 1 ) ) ) | 
						
							| 62 |  | f1ocnv |  |-  ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) -> `' F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 63 | 6 62 | syl |  |-  ( ph -> `' F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 64 |  | f1of1 |  |-  ( `' F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) -> `' F : ( M ... ( N + 1 ) ) -1-1-> ( M ... ( N + 1 ) ) ) | 
						
							| 65 | 63 64 | syl |  |-  ( ph -> `' F : ( M ... ( N + 1 ) ) -1-1-> ( M ... ( N + 1 ) ) ) | 
						
							| 66 |  | f1f |  |-  ( `' F : ( M ... ( N + 1 ) ) -1-1-> ( M ... ( N + 1 ) ) -> `' F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 67 | 65 66 | syl |  |-  ( ph -> `' F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 68 |  | peano2uz |  |-  ( N e. ( ZZ>= ` M ) -> ( N + 1 ) e. ( ZZ>= ` M ) ) | 
						
							| 69 | 4 68 | syl |  |-  ( ph -> ( N + 1 ) e. ( ZZ>= ` M ) ) | 
						
							| 70 |  | eluzfz2 |  |-  ( ( N + 1 ) e. ( ZZ>= ` M ) -> ( N + 1 ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 71 | 69 70 | syl |  |-  ( ph -> ( N + 1 ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 72 | 67 71 | ffvelcdmd |  |-  ( ph -> ( `' F ` ( N + 1 ) ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 73 | 9 72 | eqeltrid |  |-  ( ph -> K e. ( M ... ( N + 1 ) ) ) | 
						
							| 74 | 73 | elfzelzd |  |-  ( ph -> K e. ZZ ) | 
						
							| 75 | 74 | zred |  |-  ( ph -> K e. RR ) | 
						
							| 76 | 75 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> K e. RR ) | 
						
							| 77 | 21 | ad2antlr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> k e. RR ) | 
						
							| 78 |  | peano2re |  |-  ( k e. RR -> ( k + 1 ) e. RR ) | 
						
							| 79 | 77 78 | syl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( k + 1 ) e. RR ) | 
						
							| 80 |  | simprl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> -. k < K ) | 
						
							| 81 | 76 77 80 | nltled |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> K <_ k ) | 
						
							| 82 | 77 | ltp1d |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> k < ( k + 1 ) ) | 
						
							| 83 | 76 77 79 81 82 | lelttrd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> K < ( k + 1 ) ) | 
						
							| 84 | 76 83 | ltned |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> K =/= ( k + 1 ) ) | 
						
							| 85 | 26 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 86 |  | fzp1elp1 |  |-  ( k e. ( M ... N ) -> ( k + 1 ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 87 | 86 | ad2antlr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( k + 1 ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 88 | 85 87 | ffvelcdmd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( F ` ( k + 1 ) ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 89 |  | elfzp1 |  |-  ( N e. ( ZZ>= ` M ) -> ( ( F ` ( k + 1 ) ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` ( k + 1 ) ) e. ( M ... N ) \/ ( F ` ( k + 1 ) ) = ( N + 1 ) ) ) ) | 
						
							| 90 | 4 89 | syl |  |-  ( ph -> ( ( F ` ( k + 1 ) ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` ( k + 1 ) ) e. ( M ... N ) \/ ( F ` ( k + 1 ) ) = ( N + 1 ) ) ) ) | 
						
							| 91 | 90 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( F ` ( k + 1 ) ) e. ( M ... ( N + 1 ) ) <-> ( ( F ` ( k + 1 ) ) e. ( M ... N ) \/ ( F ` ( k + 1 ) ) = ( N + 1 ) ) ) ) | 
						
							| 92 | 88 91 | mpbid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( F ` ( k + 1 ) ) e. ( M ... N ) \/ ( F ` ( k + 1 ) ) = ( N + 1 ) ) ) | 
						
							| 93 | 92 | ord |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( -. ( F ` ( k + 1 ) ) e. ( M ... N ) -> ( F ` ( k + 1 ) ) = ( N + 1 ) ) ) | 
						
							| 94 | 6 | ad2antrr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 95 |  | f1ocnvfv |  |-  ( ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) /\ ( k + 1 ) e. ( M ... ( N + 1 ) ) ) -> ( ( F ` ( k + 1 ) ) = ( N + 1 ) -> ( `' F ` ( N + 1 ) ) = ( k + 1 ) ) ) | 
						
							| 96 | 94 87 95 | syl2anc |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( F ` ( k + 1 ) ) = ( N + 1 ) -> ( `' F ` ( N + 1 ) ) = ( k + 1 ) ) ) | 
						
							| 97 | 9 | eqeq1i |  |-  ( K = ( k + 1 ) <-> ( `' F ` ( N + 1 ) ) = ( k + 1 ) ) | 
						
							| 98 | 96 97 | imbitrrdi |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( F ` ( k + 1 ) ) = ( N + 1 ) -> K = ( k + 1 ) ) ) | 
						
							| 99 | 93 98 | syld |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( -. ( F ` ( k + 1 ) ) e. ( M ... N ) -> K = ( k + 1 ) ) ) | 
						
							| 100 | 99 | necon1ad |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( K =/= ( k + 1 ) -> ( F ` ( k + 1 ) ) e. ( M ... N ) ) ) | 
						
							| 101 | 84 100 | mpd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( F ` ( k + 1 ) ) e. ( M ... N ) ) | 
						
							| 102 | 61 101 | eqeltrd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> x e. ( M ... N ) ) | 
						
							| 103 | 61 | eqcomd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( F ` ( k + 1 ) ) = x ) | 
						
							| 104 |  | f1ocnvfv |  |-  ( ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) /\ ( k + 1 ) e. ( M ... ( N + 1 ) ) ) -> ( ( F ` ( k + 1 ) ) = x -> ( `' F ` x ) = ( k + 1 ) ) ) | 
						
							| 105 | 94 87 104 | syl2anc |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( F ` ( k + 1 ) ) = x -> ( `' F ` x ) = ( k + 1 ) ) ) | 
						
							| 106 | 103 105 | mpd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( `' F ` x ) = ( k + 1 ) ) | 
						
							| 107 | 106 | breq1d |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( `' F ` x ) < K <-> ( k + 1 ) < K ) ) | 
						
							| 108 |  | lttr |  |-  ( ( k e. RR /\ ( k + 1 ) e. RR /\ K e. RR ) -> ( ( k < ( k + 1 ) /\ ( k + 1 ) < K ) -> k < K ) ) | 
						
							| 109 | 77 79 76 108 | syl3anc |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( k < ( k + 1 ) /\ ( k + 1 ) < K ) -> k < K ) ) | 
						
							| 110 | 82 109 | mpand |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( k + 1 ) < K -> k < K ) ) | 
						
							| 111 | 107 110 | sylbid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( `' F ` x ) < K -> k < K ) ) | 
						
							| 112 | 80 111 | mtod |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> -. ( `' F ` x ) < K ) | 
						
							| 113 |  | iffalse |  |-  ( -. ( `' F ` x ) < K -> if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) = ( ( `' F ` x ) - 1 ) ) | 
						
							| 114 | 112 113 | syl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) = ( ( `' F ` x ) - 1 ) ) | 
						
							| 115 | 106 | oveq1d |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( `' F ` x ) - 1 ) = ( ( k + 1 ) - 1 ) ) | 
						
							| 116 | 77 | recnd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> k e. CC ) | 
						
							| 117 |  | ax-1cn |  |-  1 e. CC | 
						
							| 118 |  | pncan |  |-  ( ( k e. CC /\ 1 e. CC ) -> ( ( k + 1 ) - 1 ) = k ) | 
						
							| 119 | 116 117 118 | sylancl |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( ( k + 1 ) - 1 ) = k ) | 
						
							| 120 | 114 115 119 | 3eqtrrd |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 121 | 102 120 | jca |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ ( -. k < K /\ x = ( F ` ( k + 1 ) ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) | 
						
							| 122 | 121 | expr |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ -. k < K ) -> ( x = ( F ` ( k + 1 ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 123 | 60 122 | sylbid |  |-  ( ( ( ph /\ k e. ( M ... N ) ) /\ -. k < K ) -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 124 | 56 123 | pm2.61dan |  |-  ( ( ph /\ k e. ( M ... N ) ) -> ( x = ( F ` if ( k < K , k , ( k + 1 ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 125 | 124 | expimpd |  |-  ( ph -> ( ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) -> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 126 | 51 | eqeq2d |  |-  ( ( `' F ` x ) < K -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) <-> k = ( `' F ` x ) ) ) | 
						
							| 127 | 126 | adantl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( `' F ` x ) < K ) -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) <-> k = ( `' F ` x ) ) ) | 
						
							| 128 |  | eluzel2 |  |-  ( N e. ( ZZ>= ` M ) -> M e. ZZ ) | 
						
							| 129 | 4 128 | syl |  |-  ( ph -> M e. ZZ ) | 
						
							| 130 | 129 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> M e. ZZ ) | 
						
							| 131 |  | eluzelz |  |-  ( N e. ( ZZ>= ` M ) -> N e. ZZ ) | 
						
							| 132 | 4 131 | syl |  |-  ( ph -> N e. ZZ ) | 
						
							| 133 | 132 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> N e. ZZ ) | 
						
							| 134 |  | simprr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k = ( `' F ` x ) ) | 
						
							| 135 | 67 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> `' F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 136 |  | simplr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> x e. ( M ... N ) ) | 
						
							| 137 | 28 136 | sselid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> x e. ( M ... ( N + 1 ) ) ) | 
						
							| 138 | 135 137 | ffvelcdmd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( `' F ` x ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 139 | 134 138 | eqeltrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k e. ( M ... ( N + 1 ) ) ) | 
						
							| 140 | 139 | elfzelzd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k e. ZZ ) | 
						
							| 141 |  | elfzle1 |  |-  ( k e. ( M ... ( N + 1 ) ) -> M <_ k ) | 
						
							| 142 | 139 141 | syl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> M <_ k ) | 
						
							| 143 | 140 | zred |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k e. RR ) | 
						
							| 144 | 75 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> K e. RR ) | 
						
							| 145 | 132 | peano2zd |  |-  ( ph -> ( N + 1 ) e. ZZ ) | 
						
							| 146 | 145 | zred |  |-  ( ph -> ( N + 1 ) e. RR ) | 
						
							| 147 | 146 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( N + 1 ) e. RR ) | 
						
							| 148 |  | simprl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( `' F ` x ) < K ) | 
						
							| 149 | 134 148 | eqbrtrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k < K ) | 
						
							| 150 |  | elfzle2 |  |-  ( K e. ( M ... ( N + 1 ) ) -> K <_ ( N + 1 ) ) | 
						
							| 151 | 73 150 | syl |  |-  ( ph -> K <_ ( N + 1 ) ) | 
						
							| 152 | 151 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> K <_ ( N + 1 ) ) | 
						
							| 153 | 143 144 147 149 152 | ltletrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k < ( N + 1 ) ) | 
						
							| 154 |  | zleltp1 |  |-  ( ( k e. ZZ /\ N e. ZZ ) -> ( k <_ N <-> k < ( N + 1 ) ) ) | 
						
							| 155 | 140 133 154 | syl2anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( k <_ N <-> k < ( N + 1 ) ) ) | 
						
							| 156 | 153 155 | mpbird |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k <_ N ) | 
						
							| 157 | 130 133 140 142 156 | elfzd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> k e. ( M ... N ) ) | 
						
							| 158 | 149 16 | syl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( F ` if ( k < K , k , ( k + 1 ) ) ) = ( F ` k ) ) | 
						
							| 159 | 134 | fveq2d |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( F ` k ) = ( F ` ( `' F ` x ) ) ) | 
						
							| 160 | 6 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 161 |  | f1ocnvfv2 |  |-  ( ( F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) /\ x e. ( M ... ( N + 1 ) ) ) -> ( F ` ( `' F ` x ) ) = x ) | 
						
							| 162 | 160 137 161 | syl2anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( F ` ( `' F ` x ) ) = x ) | 
						
							| 163 | 158 159 162 | 3eqtrrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) | 
						
							| 164 | 157 163 | jca |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( ( `' F ` x ) < K /\ k = ( `' F ` x ) ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) | 
						
							| 165 | 164 | expr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( `' F ` x ) < K ) -> ( k = ( `' F ` x ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 166 | 127 165 | sylbid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( `' F ` x ) < K ) -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 167 | 113 | eqeq2d |  |-  ( -. ( `' F ` x ) < K -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) <-> k = ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 168 | 167 | adantl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ -. ( `' F ` x ) < K ) -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) <-> k = ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 169 | 129 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> M e. ZZ ) | 
						
							| 170 | 132 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> N e. ZZ ) | 
						
							| 171 |  | simprr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> k = ( ( `' F ` x ) - 1 ) ) | 
						
							| 172 | 67 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> `' F : ( M ... ( N + 1 ) ) --> ( M ... ( N + 1 ) ) ) | 
						
							| 173 |  | simplr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> x e. ( M ... N ) ) | 
						
							| 174 | 28 173 | sselid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> x e. ( M ... ( N + 1 ) ) ) | 
						
							| 175 | 172 174 | ffvelcdmd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 176 | 175 | elfzelzd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) e. ZZ ) | 
						
							| 177 |  | peano2zm |  |-  ( ( `' F ` x ) e. ZZ -> ( ( `' F ` x ) - 1 ) e. ZZ ) | 
						
							| 178 | 176 177 | syl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( `' F ` x ) - 1 ) e. ZZ ) | 
						
							| 179 | 171 178 | eqeltrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> k e. ZZ ) | 
						
							| 180 | 129 | zred |  |-  ( ph -> M e. RR ) | 
						
							| 181 | 180 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> M e. RR ) | 
						
							| 182 | 75 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K e. RR ) | 
						
							| 183 | 179 | zred |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> k e. RR ) | 
						
							| 184 |  | elfzle1 |  |-  ( K e. ( M ... ( N + 1 ) ) -> M <_ K ) | 
						
							| 185 | 73 184 | syl |  |-  ( ph -> M <_ K ) | 
						
							| 186 | 185 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> M <_ K ) | 
						
							| 187 | 176 | zred |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) e. RR ) | 
						
							| 188 |  | simprl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> -. ( `' F ` x ) < K ) | 
						
							| 189 | 182 187 188 | nltled |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K <_ ( `' F ` x ) ) | 
						
							| 190 |  | elfzelz |  |-  ( x e. ( M ... N ) -> x e. ZZ ) | 
						
							| 191 | 190 | adantl |  |-  ( ( ph /\ x e. ( M ... N ) ) -> x e. ZZ ) | 
						
							| 192 | 191 | zred |  |-  ( ( ph /\ x e. ( M ... N ) ) -> x e. RR ) | 
						
							| 193 | 132 | zred |  |-  ( ph -> N e. RR ) | 
						
							| 194 | 193 | adantr |  |-  ( ( ph /\ x e. ( M ... N ) ) -> N e. RR ) | 
						
							| 195 | 146 | adantr |  |-  ( ( ph /\ x e. ( M ... N ) ) -> ( N + 1 ) e. RR ) | 
						
							| 196 |  | elfzle2 |  |-  ( x e. ( M ... N ) -> x <_ N ) | 
						
							| 197 | 196 | adantl |  |-  ( ( ph /\ x e. ( M ... N ) ) -> x <_ N ) | 
						
							| 198 | 194 | ltp1d |  |-  ( ( ph /\ x e. ( M ... N ) ) -> N < ( N + 1 ) ) | 
						
							| 199 | 192 194 195 197 198 | lelttrd |  |-  ( ( ph /\ x e. ( M ... N ) ) -> x < ( N + 1 ) ) | 
						
							| 200 | 192 199 | gtned |  |-  ( ( ph /\ x e. ( M ... N ) ) -> ( N + 1 ) =/= x ) | 
						
							| 201 | 200 | adantr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( N + 1 ) =/= x ) | 
						
							| 202 | 65 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> `' F : ( M ... ( N + 1 ) ) -1-1-> ( M ... ( N + 1 ) ) ) | 
						
							| 203 | 71 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( N + 1 ) e. ( M ... ( N + 1 ) ) ) | 
						
							| 204 |  | f1fveq |  |-  ( ( `' F : ( M ... ( N + 1 ) ) -1-1-> ( M ... ( N + 1 ) ) /\ ( ( N + 1 ) e. ( M ... ( N + 1 ) ) /\ x e. ( M ... ( N + 1 ) ) ) ) -> ( ( `' F ` ( N + 1 ) ) = ( `' F ` x ) <-> ( N + 1 ) = x ) ) | 
						
							| 205 | 202 203 174 204 | syl12anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( `' F ` ( N + 1 ) ) = ( `' F ` x ) <-> ( N + 1 ) = x ) ) | 
						
							| 206 | 205 | necon3bid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( `' F ` ( N + 1 ) ) =/= ( `' F ` x ) <-> ( N + 1 ) =/= x ) ) | 
						
							| 207 | 201 206 | mpbird |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` ( N + 1 ) ) =/= ( `' F ` x ) ) | 
						
							| 208 | 9 | neeq1i |  |-  ( K =/= ( `' F ` x ) <-> ( `' F ` ( N + 1 ) ) =/= ( `' F ` x ) ) | 
						
							| 209 | 207 208 | sylibr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K =/= ( `' F ` x ) ) | 
						
							| 210 | 209 | necomd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) =/= K ) | 
						
							| 211 | 182 187 189 210 | leneltd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K < ( `' F ` x ) ) | 
						
							| 212 | 74 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K e. ZZ ) | 
						
							| 213 |  | zltlem1 |  |-  ( ( K e. ZZ /\ ( `' F ` x ) e. ZZ ) -> ( K < ( `' F ` x ) <-> K <_ ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 214 | 212 176 213 | syl2anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( K < ( `' F ` x ) <-> K <_ ( ( `' F ` x ) - 1 ) ) ) | 
						
							| 215 | 211 214 | mpbid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K <_ ( ( `' F ` x ) - 1 ) ) | 
						
							| 216 | 215 171 | breqtrrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> K <_ k ) | 
						
							| 217 | 181 182 183 186 216 | letrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> M <_ k ) | 
						
							| 218 |  | elfzle2 |  |-  ( ( `' F ` x ) e. ( M ... ( N + 1 ) ) -> ( `' F ` x ) <_ ( N + 1 ) ) | 
						
							| 219 | 175 218 | syl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) <_ ( N + 1 ) ) | 
						
							| 220 | 193 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> N e. RR ) | 
						
							| 221 |  | 1re |  |-  1 e. RR | 
						
							| 222 |  | lesubadd |  |-  ( ( ( `' F ` x ) e. RR /\ 1 e. RR /\ N e. RR ) -> ( ( ( `' F ` x ) - 1 ) <_ N <-> ( `' F ` x ) <_ ( N + 1 ) ) ) | 
						
							| 223 | 221 222 | mp3an2 |  |-  ( ( ( `' F ` x ) e. RR /\ N e. RR ) -> ( ( ( `' F ` x ) - 1 ) <_ N <-> ( `' F ` x ) <_ ( N + 1 ) ) ) | 
						
							| 224 | 187 220 223 | syl2anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( ( `' F ` x ) - 1 ) <_ N <-> ( `' F ` x ) <_ ( N + 1 ) ) ) | 
						
							| 225 | 219 224 | mpbird |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( `' F ` x ) - 1 ) <_ N ) | 
						
							| 226 | 171 225 | eqbrtrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> k <_ N ) | 
						
							| 227 | 169 170 179 217 226 | elfzd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> k e. ( M ... N ) ) | 
						
							| 228 | 182 183 216 | lensymd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> -. k < K ) | 
						
							| 229 | 228 58 | syl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( F ` if ( k < K , k , ( k + 1 ) ) ) = ( F ` ( k + 1 ) ) ) | 
						
							| 230 | 171 | oveq1d |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( k + 1 ) = ( ( ( `' F ` x ) - 1 ) + 1 ) ) | 
						
							| 231 | 176 | zcnd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( `' F ` x ) e. CC ) | 
						
							| 232 |  | npcan |  |-  ( ( ( `' F ` x ) e. CC /\ 1 e. CC ) -> ( ( ( `' F ` x ) - 1 ) + 1 ) = ( `' F ` x ) ) | 
						
							| 233 | 231 117 232 | sylancl |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( ( ( `' F ` x ) - 1 ) + 1 ) = ( `' F ` x ) ) | 
						
							| 234 | 230 233 | eqtrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( k + 1 ) = ( `' F ` x ) ) | 
						
							| 235 | 234 | fveq2d |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( F ` ( k + 1 ) ) = ( F ` ( `' F ` x ) ) ) | 
						
							| 236 | 6 | ad2antrr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> F : ( M ... ( N + 1 ) ) -1-1-onto-> ( M ... ( N + 1 ) ) ) | 
						
							| 237 | 236 174 161 | syl2anc |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( F ` ( `' F ` x ) ) = x ) | 
						
							| 238 | 229 235 237 | 3eqtrrd |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) | 
						
							| 239 | 227 238 | jca |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ ( -. ( `' F ` x ) < K /\ k = ( ( `' F ` x ) - 1 ) ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) | 
						
							| 240 | 239 | expr |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ -. ( `' F ` x ) < K ) -> ( k = ( ( `' F ` x ) - 1 ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 241 | 168 240 | sylbid |  |-  ( ( ( ph /\ x e. ( M ... N ) ) /\ -. ( `' F ` x ) < K ) -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 242 | 166 241 | pm2.61dan |  |-  ( ( ph /\ x e. ( M ... N ) ) -> ( k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 243 | 242 | expimpd |  |-  ( ph -> ( ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) -> ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) ) ) | 
						
							| 244 | 125 243 | impbid |  |-  ( ph -> ( ( k e. ( M ... N ) /\ x = ( F ` if ( k < K , k , ( k + 1 ) ) ) ) <-> ( x e. ( M ... N ) /\ k = if ( ( `' F ` x ) < K , ( `' F ` x ) , ( ( `' F ` x ) - 1 ) ) ) ) ) | 
						
							| 245 | 8 10 14 244 | f1od |  |-  ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) ) |