| Step | Hyp | Ref | Expression | 
						
							| 1 |  | etransclem13.x |  |-  ( ph -> X C_ CC ) | 
						
							| 2 |  | etransclem13.p |  |-  ( ph -> P e. NN ) | 
						
							| 3 |  | etransclem13.m |  |-  ( ph -> M e. NN0 ) | 
						
							| 4 |  | etransclem13.f |  |-  F = ( x e. X |-> ( ( x ^ ( P - 1 ) ) x. prod_ j e. ( 1 ... M ) ( ( x - j ) ^ P ) ) ) | 
						
							| 5 |  | etransclem13.y |  |-  ( ph -> Y e. X ) | 
						
							| 6 |  | eqid |  |-  ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) = ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) | 
						
							| 7 |  | eqid |  |-  ( x e. X |-> prod_ j e. ( 0 ... M ) ( ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) ` x ) ) = ( x e. X |-> prod_ j e. ( 0 ... M ) ( ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) ` x ) ) | 
						
							| 8 | 1 2 3 4 6 7 | etransclem4 |  |-  ( ph -> F = ( x e. X |-> prod_ j e. ( 0 ... M ) ( ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) ` x ) ) ) | 
						
							| 9 |  | simpr |  |-  ( ( ph /\ j e. ( 0 ... M ) ) -> j e. ( 0 ... M ) ) | 
						
							| 10 |  | cnex |  |-  CC e. _V | 
						
							| 11 | 10 | ssex |  |-  ( X C_ CC -> X e. _V ) | 
						
							| 12 |  | mptexg |  |-  ( X e. _V -> ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) e. _V ) | 
						
							| 13 | 1 11 12 | 3syl |  |-  ( ph -> ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) e. _V ) | 
						
							| 14 | 13 | adantr |  |-  ( ( ph /\ j e. ( 0 ... M ) ) -> ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) e. _V ) | 
						
							| 15 |  | oveq1 |  |-  ( x = y -> ( x - j ) = ( y - j ) ) | 
						
							| 16 | 15 | oveq1d |  |-  ( x = y -> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) = ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 17 | 16 | cbvmptv |  |-  ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) = ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 18 | 17 | mpteq2i |  |-  ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) = ( j e. ( 0 ... M ) |-> ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) | 
						
							| 19 | 18 | fvmpt2 |  |-  ( ( j e. ( 0 ... M ) /\ ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) e. _V ) -> ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) = ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) | 
						
							| 20 | 9 14 19 | syl2anc |  |-  ( ( ph /\ j e. ( 0 ... M ) ) -> ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) = ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) | 
						
							| 21 | 20 | adantlr |  |-  ( ( ( ph /\ x = Y ) /\ j e. ( 0 ... M ) ) -> ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) = ( y e. X |-> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) | 
						
							| 22 |  | simpr |  |-  ( ( x = Y /\ y = x ) -> y = x ) | 
						
							| 23 |  | simpl |  |-  ( ( x = Y /\ y = x ) -> x = Y ) | 
						
							| 24 | 22 23 | eqtrd |  |-  ( ( x = Y /\ y = x ) -> y = Y ) | 
						
							| 25 |  | oveq1 |  |-  ( y = Y -> ( y - j ) = ( Y - j ) ) | 
						
							| 26 | 25 | oveq1d |  |-  ( y = Y -> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) = ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 27 | 24 26 | syl |  |-  ( ( x = Y /\ y = x ) -> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) = ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 28 | 27 | adantll |  |-  ( ( ( ph /\ x = Y ) /\ y = x ) -> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) = ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 29 | 28 | adantlr |  |-  ( ( ( ( ph /\ x = Y ) /\ j e. ( 0 ... M ) ) /\ y = x ) -> ( ( y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) = ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 30 |  | simpr |  |-  ( ( ph /\ x = Y ) -> x = Y ) | 
						
							| 31 | 5 | adantr |  |-  ( ( ph /\ x = Y ) -> Y e. X ) | 
						
							| 32 | 30 31 | eqeltrd |  |-  ( ( ph /\ x = Y ) -> x e. X ) | 
						
							| 33 | 32 | adantr |  |-  ( ( ( ph /\ x = Y ) /\ j e. ( 0 ... M ) ) -> x e. X ) | 
						
							| 34 |  | ovexd |  |-  ( ( ( ph /\ x = Y ) /\ j e. ( 0 ... M ) ) -> ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) e. _V ) | 
						
							| 35 | 21 29 33 34 | fvmptd |  |-  ( ( ( ph /\ x = Y ) /\ j e. ( 0 ... M ) ) -> ( ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) ` x ) = ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 36 | 35 | prodeq2dv |  |-  ( ( ph /\ x = Y ) -> prod_ j e. ( 0 ... M ) ( ( ( j e. ( 0 ... M ) |-> ( x e. X |-> ( ( x - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) ) ` j ) ` x ) = prod_ j e. ( 0 ... M ) ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) | 
						
							| 37 |  | prodex |  |-  prod_ j e. ( 0 ... M ) ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) e. _V | 
						
							| 38 | 37 | a1i |  |-  ( ph -> prod_ j e. ( 0 ... M ) ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) e. _V ) | 
						
							| 39 | 8 36 5 38 | fvmptd |  |-  ( ph -> ( F ` Y ) = prod_ j e. ( 0 ... M ) ( ( Y - j ) ^ if ( j = 0 , ( P - 1 ) , P ) ) ) |