| Step | Hyp | Ref | Expression | 
						
							| 1 |  | clwlkclwwlklem2.f |  |-  F = ( x e. ( 0 ..^ ( ( # ` P ) - 1 ) ) |-> if ( x < ( ( # ` P ) - 2 ) , ( `' E ` { ( P ` x ) , ( P ` ( x + 1 ) ) } ) , ( `' E ` { ( P ` x ) , ( P ` 0 ) } ) ) ) | 
						
							| 2 |  | lencl |  |-  ( P e. Word V -> ( # ` P ) e. NN0 ) | 
						
							| 3 |  | nn0z |  |-  ( ( # ` P ) e. NN0 -> ( # ` P ) e. ZZ ) | 
						
							| 4 | 3 | adantr |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> ( # ` P ) e. ZZ ) | 
						
							| 5 |  | 0red |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> 0 e. RR ) | 
						
							| 6 |  | 2re |  |-  2 e. RR | 
						
							| 7 | 6 | a1i |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> 2 e. RR ) | 
						
							| 8 |  | nn0re |  |-  ( ( # ` P ) e. NN0 -> ( # ` P ) e. RR ) | 
						
							| 9 | 8 | adantr |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> ( # ` P ) e. RR ) | 
						
							| 10 |  | 2pos |  |-  0 < 2 | 
						
							| 11 | 10 | a1i |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> 0 < 2 ) | 
						
							| 12 |  | simpr |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> 2 <_ ( # ` P ) ) | 
						
							| 13 | 5 7 9 11 12 | ltletrd |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> 0 < ( # ` P ) ) | 
						
							| 14 |  | elnnz |  |-  ( ( # ` P ) e. NN <-> ( ( # ` P ) e. ZZ /\ 0 < ( # ` P ) ) ) | 
						
							| 15 | 4 13 14 | sylanbrc |  |-  ( ( ( # ` P ) e. NN0 /\ 2 <_ ( # ` P ) ) -> ( # ` P ) e. NN ) | 
						
							| 16 | 2 15 | sylan |  |-  ( ( P e. Word V /\ 2 <_ ( # ` P ) ) -> ( # ` P ) e. NN ) | 
						
							| 17 |  | nnm1nn0 |  |-  ( ( # ` P ) e. NN -> ( ( # ` P ) - 1 ) e. NN0 ) | 
						
							| 18 | 16 17 | syl |  |-  ( ( P e. Word V /\ 2 <_ ( # ` P ) ) -> ( ( # ` P ) - 1 ) e. NN0 ) | 
						
							| 19 |  | fvex |  |-  ( `' E ` { ( P ` x ) , ( P ` ( x + 1 ) ) } ) e. _V | 
						
							| 20 |  | fvex |  |-  ( `' E ` { ( P ` x ) , ( P ` 0 ) } ) e. _V | 
						
							| 21 | 19 20 | ifex |  |-  if ( x < ( ( # ` P ) - 2 ) , ( `' E ` { ( P ` x ) , ( P ` ( x + 1 ) ) } ) , ( `' E ` { ( P ` x ) , ( P ` 0 ) } ) ) e. _V | 
						
							| 22 | 21 1 | fnmpti |  |-  F Fn ( 0 ..^ ( ( # ` P ) - 1 ) ) | 
						
							| 23 |  | ffzo0hash |  |-  ( ( ( ( # ` P ) - 1 ) e. NN0 /\ F Fn ( 0 ..^ ( ( # ` P ) - 1 ) ) ) -> ( # ` F ) = ( ( # ` P ) - 1 ) ) | 
						
							| 24 | 18 22 23 | sylancl |  |-  ( ( P e. Word V /\ 2 <_ ( # ` P ) ) -> ( # ` F ) = ( ( # ` P ) - 1 ) ) |