Metamath Proof Explorer


Theorem eulerpartleme

Description: Lemma for eulerpart . (Contributed by Mario Carneiro, 26-Jan-2015)

Ref Expression
Hypothesis eulerpart.p P = f 0 | f -1 Fin k f k k = N
Assertion eulerpartleme A P A : 0 A -1 Fin k A k k = N

Proof

Step Hyp Ref Expression
1 eulerpart.p P = f 0 | f -1 Fin k f k k = N
2 nn0ex 0 V
3 nnex V
4 2 3 elmap A 0 A : 0
5 4 anbi1i A 0 A -1 Fin k A k k = N A : 0 A -1 Fin k A k k = N
6 cnveq f = A f -1 = A -1
7 6 imaeq1d f = A f -1 = A -1
8 7 eleq1d f = A f -1 Fin A -1 Fin
9 fveq1 f = A f k = A k
10 9 oveq1d f = A f k k = A k k
11 10 sumeq2sdv f = A k f k k = k A k k
12 11 eqeq1d f = A k f k k = N k A k k = N
13 8 12 anbi12d f = A f -1 Fin k f k k = N A -1 Fin k A k k = N
14 13 1 elrab2 A P A 0 A -1 Fin k A k k = N
15 3anass A : 0 A -1 Fin k A k k = N A : 0 A -1 Fin k A k k = N
16 5 14 15 3bitr4i A P A : 0 A -1 Fin k A k k = N