| Step | Hyp | Ref | Expression | 
						
							| 1 |  | signsv.p |  |-  .+^ = ( a e. { -u 1 , 0 , 1 } , b e. { -u 1 , 0 , 1 } |-> if ( b = 0 , a , b ) ) | 
						
							| 2 |  | signsv.w |  |-  W = { <. ( Base ` ndx ) , { -u 1 , 0 , 1 } >. , <. ( +g ` ndx ) , .+^ >. } | 
						
							| 3 |  | signsv.t |  |-  T = ( f e. Word RR |-> ( n e. ( 0 ..^ ( # ` f ) ) |-> ( W gsum ( i e. ( 0 ... n ) |-> ( sgn ` ( f ` i ) ) ) ) ) ) | 
						
							| 4 |  | signsv.v |  |-  V = ( f e. Word RR |-> sum_ j e. ( 1 ..^ ( # ` f ) ) if ( ( ( T ` f ) ` j ) =/= ( ( T ` f ) ` ( j - 1 ) ) , 1 , 0 ) ) | 
						
							| 5 |  | simpl1 |  |-  ( ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) /\ i e. ( 0 ... N ) ) -> F e. Word RR ) | 
						
							| 6 |  | s1cl |  |-  ( K e. RR -> <" K "> e. Word RR ) | 
						
							| 7 | 6 | 3ad2ant2 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> <" K "> e. Word RR ) | 
						
							| 8 | 7 | adantr |  |-  ( ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) /\ i e. ( 0 ... N ) ) -> <" K "> e. Word RR ) | 
						
							| 9 |  | fzssfzo |  |-  ( N e. ( 0 ..^ ( # ` F ) ) -> ( 0 ... N ) C_ ( 0 ..^ ( # ` F ) ) ) | 
						
							| 10 | 9 | 3ad2ant3 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( 0 ... N ) C_ ( 0 ..^ ( # ` F ) ) ) | 
						
							| 11 | 10 | sselda |  |-  ( ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) /\ i e. ( 0 ... N ) ) -> i e. ( 0 ..^ ( # ` F ) ) ) | 
						
							| 12 |  | ccatval1 |  |-  ( ( F e. Word RR /\ <" K "> e. Word RR /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( ( F ++ <" K "> ) ` i ) = ( F ` i ) ) | 
						
							| 13 | 5 8 11 12 | syl3anc |  |-  ( ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) /\ i e. ( 0 ... N ) ) -> ( ( F ++ <" K "> ) ` i ) = ( F ` i ) ) | 
						
							| 14 | 13 | fveq2d |  |-  ( ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) /\ i e. ( 0 ... N ) ) -> ( sgn ` ( ( F ++ <" K "> ) ` i ) ) = ( sgn ` ( F ` i ) ) ) | 
						
							| 15 | 14 | mpteq2dva |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( i e. ( 0 ... N ) |-> ( sgn ` ( ( F ++ <" K "> ) ` i ) ) ) = ( i e. ( 0 ... N ) |-> ( sgn ` ( F ` i ) ) ) ) | 
						
							| 16 | 15 | oveq2d |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( ( F ++ <" K "> ) ` i ) ) ) ) = ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( F ` i ) ) ) ) ) | 
						
							| 17 |  | ccatws1cl |  |-  ( ( F e. Word RR /\ K e. RR ) -> ( F ++ <" K "> ) e. Word RR ) | 
						
							| 18 | 17 | 3adant3 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( F ++ <" K "> ) e. Word RR ) | 
						
							| 19 |  | lencl |  |-  ( F e. Word RR -> ( # ` F ) e. NN0 ) | 
						
							| 20 | 19 | nn0zd |  |-  ( F e. Word RR -> ( # ` F ) e. ZZ ) | 
						
							| 21 | 20 | uzidd |  |-  ( F e. Word RR -> ( # ` F ) e. ( ZZ>= ` ( # ` F ) ) ) | 
						
							| 22 |  | peano2uz |  |-  ( ( # ` F ) e. ( ZZ>= ` ( # ` F ) ) -> ( ( # ` F ) + 1 ) e. ( ZZ>= ` ( # ` F ) ) ) | 
						
							| 23 |  | fzoss2 |  |-  ( ( ( # ` F ) + 1 ) e. ( ZZ>= ` ( # ` F ) ) -> ( 0 ..^ ( # ` F ) ) C_ ( 0 ..^ ( ( # ` F ) + 1 ) ) ) | 
						
							| 24 | 21 22 23 | 3syl |  |-  ( F e. Word RR -> ( 0 ..^ ( # ` F ) ) C_ ( 0 ..^ ( ( # ` F ) + 1 ) ) ) | 
						
							| 25 | 24 | sselda |  |-  ( ( F e. Word RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> N e. ( 0 ..^ ( ( # ` F ) + 1 ) ) ) | 
						
							| 26 | 25 | 3adant2 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> N e. ( 0 ..^ ( ( # ` F ) + 1 ) ) ) | 
						
							| 27 |  | ccatlen |  |-  ( ( F e. Word RR /\ <" K "> e. Word RR ) -> ( # ` ( F ++ <" K "> ) ) = ( ( # ` F ) + ( # ` <" K "> ) ) ) | 
						
							| 28 | 6 27 | sylan2 |  |-  ( ( F e. Word RR /\ K e. RR ) -> ( # ` ( F ++ <" K "> ) ) = ( ( # ` F ) + ( # ` <" K "> ) ) ) | 
						
							| 29 | 28 | 3adant3 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( # ` ( F ++ <" K "> ) ) = ( ( # ` F ) + ( # ` <" K "> ) ) ) | 
						
							| 30 |  | s1len |  |-  ( # ` <" K "> ) = 1 | 
						
							| 31 | 30 | oveq2i |  |-  ( ( # ` F ) + ( # ` <" K "> ) ) = ( ( # ` F ) + 1 ) | 
						
							| 32 | 29 31 | eqtrdi |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( # ` ( F ++ <" K "> ) ) = ( ( # ` F ) + 1 ) ) | 
						
							| 33 | 32 | oveq2d |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( 0 ..^ ( # ` ( F ++ <" K "> ) ) ) = ( 0 ..^ ( ( # ` F ) + 1 ) ) ) | 
						
							| 34 | 26 33 | eleqtrrd |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> N e. ( 0 ..^ ( # ` ( F ++ <" K "> ) ) ) ) | 
						
							| 35 | 1 2 3 4 | signstfval |  |-  ( ( ( F ++ <" K "> ) e. Word RR /\ N e. ( 0 ..^ ( # ` ( F ++ <" K "> ) ) ) ) -> ( ( T ` ( F ++ <" K "> ) ) ` N ) = ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( ( F ++ <" K "> ) ` i ) ) ) ) ) | 
						
							| 36 | 18 34 35 | syl2anc |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( ( T ` ( F ++ <" K "> ) ) ` N ) = ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( ( F ++ <" K "> ) ` i ) ) ) ) ) | 
						
							| 37 | 1 2 3 4 | signstfval |  |-  ( ( F e. Word RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( ( T ` F ) ` N ) = ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( F ` i ) ) ) ) ) | 
						
							| 38 | 37 | 3adant2 |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( ( T ` F ) ` N ) = ( W gsum ( i e. ( 0 ... N ) |-> ( sgn ` ( F ` i ) ) ) ) ) | 
						
							| 39 | 16 36 38 | 3eqtr4d |  |-  ( ( F e. Word RR /\ K e. RR /\ N e. ( 0 ..^ ( # ` F ) ) ) -> ( ( T ` ( F ++ <" K "> ) ) ` N ) = ( ( T ` F ) ` N ) ) |