| Step | Hyp | Ref | Expression | 
						
							| 1 |  | peano2nn0 |  |-  ( K e. NN0 -> ( K + 1 ) e. NN0 ) | 
						
							| 2 |  | vdwapval |  |-  ( ( ( K + 1 ) e. NN0 /\ A e. NN /\ D e. NN ) -> ( x e. ( A ( AP ` ( K + 1 ) ) D ) <-> E. n e. ( 0 ... ( ( K + 1 ) - 1 ) ) x = ( A + ( n x. D ) ) ) ) | 
						
							| 3 | 1 2 | syl3an1 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( x e. ( A ( AP ` ( K + 1 ) ) D ) <-> E. n e. ( 0 ... ( ( K + 1 ) - 1 ) ) x = ( A + ( n x. D ) ) ) ) | 
						
							| 4 |  | simp1 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> K e. NN0 ) | 
						
							| 5 | 4 | nn0cnd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> K e. CC ) | 
						
							| 6 |  | ax-1cn |  |-  1 e. CC | 
						
							| 7 |  | pncan |  |-  ( ( K e. CC /\ 1 e. CC ) -> ( ( K + 1 ) - 1 ) = K ) | 
						
							| 8 | 5 6 7 | sylancl |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( K + 1 ) - 1 ) = K ) | 
						
							| 9 | 8 | oveq2d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( 0 ... ( ( K + 1 ) - 1 ) ) = ( 0 ... K ) ) | 
						
							| 10 | 9 | eleq2d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) <-> n e. ( 0 ... K ) ) ) | 
						
							| 11 |  | nn0uz |  |-  NN0 = ( ZZ>= ` 0 ) | 
						
							| 12 | 4 11 | eleqtrdi |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> K e. ( ZZ>= ` 0 ) ) | 
						
							| 13 |  | elfzp12 |  |-  ( K e. ( ZZ>= ` 0 ) -> ( n e. ( 0 ... K ) <-> ( n = 0 \/ n e. ( ( 0 + 1 ) ... K ) ) ) ) | 
						
							| 14 | 12 13 | syl |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( n e. ( 0 ... K ) <-> ( n = 0 \/ n e. ( ( 0 + 1 ) ... K ) ) ) ) | 
						
							| 15 | 10 14 | bitrd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) <-> ( n = 0 \/ n e. ( ( 0 + 1 ) ... K ) ) ) ) | 
						
							| 16 | 15 | anbi1d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) /\ x = ( A + ( n x. D ) ) ) <-> ( ( n = 0 \/ n e. ( ( 0 + 1 ) ... K ) ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 17 |  | andir |  |-  ( ( ( n = 0 \/ n e. ( ( 0 + 1 ) ... K ) ) /\ x = ( A + ( n x. D ) ) ) <-> ( ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 18 | 16 17 | bitrdi |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) /\ x = ( A + ( n x. D ) ) ) <-> ( ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) ) | 
						
							| 19 | 18 | exbidv |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) /\ x = ( A + ( n x. D ) ) ) <-> E. n ( ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) ) | 
						
							| 20 |  | df-rex |  |-  ( E. n e. ( 0 ... ( ( K + 1 ) - 1 ) ) x = ( A + ( n x. D ) ) <-> E. n ( n e. ( 0 ... ( ( K + 1 ) - 1 ) ) /\ x = ( A + ( n x. D ) ) ) ) | 
						
							| 21 |  | 19.43 |  |-  ( E. n ( ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) <-> ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 22 | 21 | bicomi |  |-  ( ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) <-> E. n ( ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 23 | 19 20 22 | 3bitr4g |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n e. ( 0 ... ( ( K + 1 ) - 1 ) ) x = ( A + ( n x. D ) ) <-> ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) ) | 
						
							| 24 | 3 23 | bitrd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( x e. ( A ( AP ` ( K + 1 ) ) D ) <-> ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) ) | 
						
							| 25 |  | nncn |  |-  ( D e. NN -> D e. CC ) | 
						
							| 26 | 25 | 3ad2ant3 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> D e. CC ) | 
						
							| 27 | 26 | mul02d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( 0 x. D ) = 0 ) | 
						
							| 28 | 27 | oveq2d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( A + ( 0 x. D ) ) = ( A + 0 ) ) | 
						
							| 29 |  | nncn |  |-  ( A e. NN -> A e. CC ) | 
						
							| 30 | 29 | 3ad2ant2 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> A e. CC ) | 
						
							| 31 | 30 | addridd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( A + 0 ) = A ) | 
						
							| 32 | 28 31 | eqtrd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( A + ( 0 x. D ) ) = A ) | 
						
							| 33 | 32 | eqeq2d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( x = ( A + ( 0 x. D ) ) <-> x = A ) ) | 
						
							| 34 |  | c0ex |  |-  0 e. _V | 
						
							| 35 |  | oveq1 |  |-  ( n = 0 -> ( n x. D ) = ( 0 x. D ) ) | 
						
							| 36 | 35 | oveq2d |  |-  ( n = 0 -> ( A + ( n x. D ) ) = ( A + ( 0 x. D ) ) ) | 
						
							| 37 | 36 | eqeq2d |  |-  ( n = 0 -> ( x = ( A + ( n x. D ) ) <-> x = ( A + ( 0 x. D ) ) ) ) | 
						
							| 38 | 34 37 | ceqsexv |  |-  ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) <-> x = ( A + ( 0 x. D ) ) ) | 
						
							| 39 |  | velsn |  |-  ( x e. { A } <-> x = A ) | 
						
							| 40 | 33 38 39 | 3bitr4g |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) <-> x e. { A } ) ) | 
						
							| 41 |  | simpr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> n e. ( ( 0 + 1 ) ... K ) ) | 
						
							| 42 |  | 0p1e1 |  |-  ( 0 + 1 ) = 1 | 
						
							| 43 | 42 | oveq1i |  |-  ( ( 0 + 1 ) ... K ) = ( 1 ... K ) | 
						
							| 44 | 41 43 | eleqtrdi |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> n e. ( 1 ... K ) ) | 
						
							| 45 |  | 1zzd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> 1 e. ZZ ) | 
						
							| 46 | 4 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> K e. NN0 ) | 
						
							| 47 | 46 | nn0zd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> K e. ZZ ) | 
						
							| 48 |  | elfzelz |  |-  ( n e. ( ( 0 + 1 ) ... K ) -> n e. ZZ ) | 
						
							| 49 | 48 | adantl |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> n e. ZZ ) | 
						
							| 50 |  | fzsubel |  |-  ( ( ( 1 e. ZZ /\ K e. ZZ ) /\ ( n e. ZZ /\ 1 e. ZZ ) ) -> ( n e. ( 1 ... K ) <-> ( n - 1 ) e. ( ( 1 - 1 ) ... ( K - 1 ) ) ) ) | 
						
							| 51 | 45 47 49 45 50 | syl22anc |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n e. ( 1 ... K ) <-> ( n - 1 ) e. ( ( 1 - 1 ) ... ( K - 1 ) ) ) ) | 
						
							| 52 | 44 51 | mpbid |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n - 1 ) e. ( ( 1 - 1 ) ... ( K - 1 ) ) ) | 
						
							| 53 |  | 1m1e0 |  |-  ( 1 - 1 ) = 0 | 
						
							| 54 | 53 | oveq1i |  |-  ( ( 1 - 1 ) ... ( K - 1 ) ) = ( 0 ... ( K - 1 ) ) | 
						
							| 55 | 52 54 | eleqtrdi |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n - 1 ) e. ( 0 ... ( K - 1 ) ) ) | 
						
							| 56 | 49 | zcnd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> n e. CC ) | 
						
							| 57 |  | 1cnd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> 1 e. CC ) | 
						
							| 58 | 26 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> D e. CC ) | 
						
							| 59 | 56 57 58 | subdird |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( ( n - 1 ) x. D ) = ( ( n x. D ) - ( 1 x. D ) ) ) | 
						
							| 60 | 58 | mullidd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( 1 x. D ) = D ) | 
						
							| 61 | 60 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( ( n x. D ) - ( 1 x. D ) ) = ( ( n x. D ) - D ) ) | 
						
							| 62 | 59 61 | eqtrd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( ( n - 1 ) x. D ) = ( ( n x. D ) - D ) ) | 
						
							| 63 | 62 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( D + ( ( n - 1 ) x. D ) ) = ( D + ( ( n x. D ) - D ) ) ) | 
						
							| 64 | 56 58 | mulcld |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n x. D ) e. CC ) | 
						
							| 65 | 58 64 | pncan3d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( D + ( ( n x. D ) - D ) ) = ( n x. D ) ) | 
						
							| 66 | 63 65 | eqtr2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n x. D ) = ( D + ( ( n - 1 ) x. D ) ) ) | 
						
							| 67 | 66 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( A + ( n x. D ) ) = ( A + ( D + ( ( n - 1 ) x. D ) ) ) ) | 
						
							| 68 | 30 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> A e. CC ) | 
						
							| 69 |  | subcl |  |-  ( ( n e. CC /\ 1 e. CC ) -> ( n - 1 ) e. CC ) | 
						
							| 70 | 56 6 69 | sylancl |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( n - 1 ) e. CC ) | 
						
							| 71 | 70 58 | mulcld |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( ( n - 1 ) x. D ) e. CC ) | 
						
							| 72 | 68 58 71 | addassd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( ( A + D ) + ( ( n - 1 ) x. D ) ) = ( A + ( D + ( ( n - 1 ) x. D ) ) ) ) | 
						
							| 73 | 67 72 | eqtr4d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( A + ( n x. D ) ) = ( ( A + D ) + ( ( n - 1 ) x. D ) ) ) | 
						
							| 74 |  | oveq1 |  |-  ( m = ( n - 1 ) -> ( m x. D ) = ( ( n - 1 ) x. D ) ) | 
						
							| 75 | 74 | oveq2d |  |-  ( m = ( n - 1 ) -> ( ( A + D ) + ( m x. D ) ) = ( ( A + D ) + ( ( n - 1 ) x. D ) ) ) | 
						
							| 76 | 75 | rspceeqv |  |-  ( ( ( n - 1 ) e. ( 0 ... ( K - 1 ) ) /\ ( A + ( n x. D ) ) = ( ( A + D ) + ( ( n - 1 ) x. D ) ) ) -> E. m e. ( 0 ... ( K - 1 ) ) ( A + ( n x. D ) ) = ( ( A + D ) + ( m x. D ) ) ) | 
						
							| 77 | 55 73 76 | syl2anc |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> E. m e. ( 0 ... ( K - 1 ) ) ( A + ( n x. D ) ) = ( ( A + D ) + ( m x. D ) ) ) | 
						
							| 78 |  | eqeq1 |  |-  ( x = ( A + ( n x. D ) ) -> ( x = ( ( A + D ) + ( m x. D ) ) <-> ( A + ( n x. D ) ) = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 79 | 78 | rexbidv |  |-  ( x = ( A + ( n x. D ) ) -> ( E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) <-> E. m e. ( 0 ... ( K - 1 ) ) ( A + ( n x. D ) ) = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 80 | 77 79 | syl5ibrcom |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ n e. ( ( 0 + 1 ) ... K ) ) -> ( x = ( A + ( n x. D ) ) -> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 81 | 80 | expimpd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) -> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 82 | 81 | exlimdv |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) -> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 83 |  | simpr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> m e. ( 0 ... ( K - 1 ) ) ) | 
						
							| 84 |  | 0zd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> 0 e. ZZ ) | 
						
							| 85 | 4 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> K e. NN0 ) | 
						
							| 86 | 85 | nn0zd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> K e. ZZ ) | 
						
							| 87 |  | peano2zm |  |-  ( K e. ZZ -> ( K - 1 ) e. ZZ ) | 
						
							| 88 | 86 87 | syl |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( K - 1 ) e. ZZ ) | 
						
							| 89 |  | elfzelz |  |-  ( m e. ( 0 ... ( K - 1 ) ) -> m e. ZZ ) | 
						
							| 90 | 89 | adantl |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> m e. ZZ ) | 
						
							| 91 |  | 1zzd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> 1 e. ZZ ) | 
						
							| 92 |  | fzaddel |  |-  ( ( ( 0 e. ZZ /\ ( K - 1 ) e. ZZ ) /\ ( m e. ZZ /\ 1 e. ZZ ) ) -> ( m e. ( 0 ... ( K - 1 ) ) <-> ( m + 1 ) e. ( ( 0 + 1 ) ... ( ( K - 1 ) + 1 ) ) ) ) | 
						
							| 93 | 84 88 90 91 92 | syl22anc |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( m e. ( 0 ... ( K - 1 ) ) <-> ( m + 1 ) e. ( ( 0 + 1 ) ... ( ( K - 1 ) + 1 ) ) ) ) | 
						
							| 94 | 83 93 | mpbid |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( m + 1 ) e. ( ( 0 + 1 ) ... ( ( K - 1 ) + 1 ) ) ) | 
						
							| 95 | 85 | nn0cnd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> K e. CC ) | 
						
							| 96 |  | npcan |  |-  ( ( K e. CC /\ 1 e. CC ) -> ( ( K - 1 ) + 1 ) = K ) | 
						
							| 97 | 95 6 96 | sylancl |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( K - 1 ) + 1 ) = K ) | 
						
							| 98 | 97 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( 0 + 1 ) ... ( ( K - 1 ) + 1 ) ) = ( ( 0 + 1 ) ... K ) ) | 
						
							| 99 | 94 98 | eleqtrd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( m + 1 ) e. ( ( 0 + 1 ) ... K ) ) | 
						
							| 100 | 30 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> A e. CC ) | 
						
							| 101 | 26 | adantr |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> D e. CC ) | 
						
							| 102 | 90 | zcnd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> m e. CC ) | 
						
							| 103 | 102 101 | mulcld |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( m x. D ) e. CC ) | 
						
							| 104 | 100 101 103 | addassd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( A + D ) + ( m x. D ) ) = ( A + ( D + ( m x. D ) ) ) ) | 
						
							| 105 |  | 1cnd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> 1 e. CC ) | 
						
							| 106 | 102 105 101 | adddird |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( m + 1 ) x. D ) = ( ( m x. D ) + ( 1 x. D ) ) ) | 
						
							| 107 | 101 103 | addcomd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( D + ( m x. D ) ) = ( ( m x. D ) + D ) ) | 
						
							| 108 | 101 | mullidd |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( 1 x. D ) = D ) | 
						
							| 109 | 108 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( m x. D ) + ( 1 x. D ) ) = ( ( m x. D ) + D ) ) | 
						
							| 110 | 107 109 | eqtr4d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( D + ( m x. D ) ) = ( ( m x. D ) + ( 1 x. D ) ) ) | 
						
							| 111 | 106 110 | eqtr4d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( m + 1 ) x. D ) = ( D + ( m x. D ) ) ) | 
						
							| 112 | 111 | oveq2d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( A + ( ( m + 1 ) x. D ) ) = ( A + ( D + ( m x. D ) ) ) ) | 
						
							| 113 | 104 112 | eqtr4d |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( ( A + D ) + ( m x. D ) ) = ( A + ( ( m + 1 ) x. D ) ) ) | 
						
							| 114 |  | ovex |  |-  ( m + 1 ) e. _V | 
						
							| 115 |  | eleq1 |  |-  ( n = ( m + 1 ) -> ( n e. ( ( 0 + 1 ) ... K ) <-> ( m + 1 ) e. ( ( 0 + 1 ) ... K ) ) ) | 
						
							| 116 |  | oveq1 |  |-  ( n = ( m + 1 ) -> ( n x. D ) = ( ( m + 1 ) x. D ) ) | 
						
							| 117 | 116 | oveq2d |  |-  ( n = ( m + 1 ) -> ( A + ( n x. D ) ) = ( A + ( ( m + 1 ) x. D ) ) ) | 
						
							| 118 | 117 | eqeq2d |  |-  ( n = ( m + 1 ) -> ( ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) <-> ( ( A + D ) + ( m x. D ) ) = ( A + ( ( m + 1 ) x. D ) ) ) ) | 
						
							| 119 | 115 118 | anbi12d |  |-  ( n = ( m + 1 ) -> ( ( n e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) <-> ( ( m + 1 ) e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( ( m + 1 ) x. D ) ) ) ) ) | 
						
							| 120 | 114 119 | spcev |  |-  ( ( ( m + 1 ) e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( ( m + 1 ) x. D ) ) ) -> E. n ( n e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) ) | 
						
							| 121 | 99 113 120 | syl2anc |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> E. n ( n e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) ) | 
						
							| 122 |  | eqeq1 |  |-  ( x = ( ( A + D ) + ( m x. D ) ) -> ( x = ( A + ( n x. D ) ) <-> ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) ) | 
						
							| 123 | 122 | anbi2d |  |-  ( x = ( ( A + D ) + ( m x. D ) ) -> ( ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) <-> ( n e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) ) ) | 
						
							| 124 | 123 | exbidv |  |-  ( x = ( ( A + D ) + ( m x. D ) ) -> ( E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) <-> E. n ( n e. ( ( 0 + 1 ) ... K ) /\ ( ( A + D ) + ( m x. D ) ) = ( A + ( n x. D ) ) ) ) ) | 
						
							| 125 | 121 124 | syl5ibrcom |  |-  ( ( ( K e. NN0 /\ A e. NN /\ D e. NN ) /\ m e. ( 0 ... ( K - 1 ) ) ) -> ( x = ( ( A + D ) + ( m x. D ) ) -> E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 126 | 125 | rexlimdva |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) -> E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) ) | 
						
							| 127 | 82 126 | impbid |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) <-> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 128 |  | nnaddcl |  |-  ( ( A e. NN /\ D e. NN ) -> ( A + D ) e. NN ) | 
						
							| 129 | 128 | 3adant1 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( A + D ) e. NN ) | 
						
							| 130 |  | vdwapval |  |-  ( ( K e. NN0 /\ ( A + D ) e. NN /\ D e. NN ) -> ( x e. ( ( A + D ) ( AP ` K ) D ) <-> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 131 | 129 130 | syld3an2 |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( x e. ( ( A + D ) ( AP ` K ) D ) <-> E. m e. ( 0 ... ( K - 1 ) ) x = ( ( A + D ) + ( m x. D ) ) ) ) | 
						
							| 132 | 127 131 | bitr4d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) <-> x e. ( ( A + D ) ( AP ` K ) D ) ) ) | 
						
							| 133 | 40 132 | orbi12d |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) <-> ( x e. { A } \/ x e. ( ( A + D ) ( AP ` K ) D ) ) ) ) | 
						
							| 134 |  | elun |  |-  ( x e. ( { A } u. ( ( A + D ) ( AP ` K ) D ) ) <-> ( x e. { A } \/ x e. ( ( A + D ) ( AP ` K ) D ) ) ) | 
						
							| 135 | 133 134 | bitr4di |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( ( E. n ( n = 0 /\ x = ( A + ( n x. D ) ) ) \/ E. n ( n e. ( ( 0 + 1 ) ... K ) /\ x = ( A + ( n x. D ) ) ) ) <-> x e. ( { A } u. ( ( A + D ) ( AP ` K ) D ) ) ) ) | 
						
							| 136 | 24 135 | bitrd |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( x e. ( A ( AP ` ( K + 1 ) ) D ) <-> x e. ( { A } u. ( ( A + D ) ( AP ` K ) D ) ) ) ) | 
						
							| 137 | 136 | eqrdv |  |-  ( ( K e. NN0 /\ A e. NN /\ D e. NN ) -> ( A ( AP ` ( K + 1 ) ) D ) = ( { A } u. ( ( A + D ) ( AP ` K ) D ) ) ) |