| Step | Hyp | Ref | Expression | 
						
							| 1 |  | etransclem16.c |  |-  C = ( n e. NN0 |-> { c e. ( ( 0 ... n ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = n } ) | 
						
							| 2 |  | etransclem16.n |  |-  ( ph -> N e. NN0 ) | 
						
							| 3 | 1 2 | etransclem12 |  |-  ( ph -> ( C ` N ) = { c e. ( ( 0 ... N ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = N } ) | 
						
							| 4 |  | fzfi |  |-  ( 0 ... N ) e. Fin | 
						
							| 5 |  | fzfi |  |-  ( 0 ... M ) e. Fin | 
						
							| 6 |  | mapfi |  |-  ( ( ( 0 ... N ) e. Fin /\ ( 0 ... M ) e. Fin ) -> ( ( 0 ... N ) ^m ( 0 ... M ) ) e. Fin ) | 
						
							| 7 | 4 5 6 | mp2an |  |-  ( ( 0 ... N ) ^m ( 0 ... M ) ) e. Fin | 
						
							| 8 |  | ssrab2 |  |-  { c e. ( ( 0 ... N ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = N } C_ ( ( 0 ... N ) ^m ( 0 ... M ) ) | 
						
							| 9 |  | ssfi |  |-  ( ( ( ( 0 ... N ) ^m ( 0 ... M ) ) e. Fin /\ { c e. ( ( 0 ... N ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = N } C_ ( ( 0 ... N ) ^m ( 0 ... M ) ) ) -> { c e. ( ( 0 ... N ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = N } e. Fin ) | 
						
							| 10 | 7 8 9 | mp2an |  |-  { c e. ( ( 0 ... N ) ^m ( 0 ... M ) ) | sum_ j e. ( 0 ... M ) ( c ` j ) = N } e. Fin | 
						
							| 11 | 3 10 | eqeltrdi |  |-  ( ph -> ( C ` N ) e. Fin ) |