Metamath Proof Explorer


Theorem etransclem12

Description: C applied to N . (Contributed by Glauco Siliprandi, 5-Apr-2020)

Ref Expression
Hypotheses etransclem12.1 ⊢ C = n ∈ ℕ 0 ⟼ c ∈ 0 … n 0 … M | ∑ j = 0 M c ⁡ j = n
etransclem12.2 ⊢ φ → N ∈ ℕ 0
Assertion etransclem12 ⊢ φ → C ⁡ N = c ∈ 0 … N 0 … M | ∑ j = 0 M c ⁡ j = N

Proof

Step Hyp Ref Expression
1 etransclem12.1 ⊢ C = n ∈ ℕ 0 ⟼ c ∈ 0 … n 0 … M | ∑ j = 0 M c ⁡ j = n
2 etransclem12.2 ⊢ φ → N ∈ ℕ 0
3 oveq2 ⊢ n = N → 0 … n = 0 … N
4 3 oveq1d ⊢ n = N → 0 … n 0 … M = 0 … N 0 … M
5 eqeq2 ⊢ n = N → ∑ j = 0 M c ⁡ j = n ↔ ∑ j = 0 M c ⁡ j = N
6 4 5 rabeqbidv ⊢ n = N → c ∈ 0 … n 0 … M | ∑ j = 0 M c ⁡ j = n = c ∈ 0 … N 0 … M | ∑ j = 0 M c ⁡ j = N
7 ovex ⊢ 0 … N 0 … M ∈ V
8 7 rabex ⊢ c ∈ 0 … N 0 … M | ∑ j = 0 M c ⁡ j = N ∈ V
9 8 a1i ⊢ φ → c ∈ 0 … N 0 … M | ∑ j = 0 M c ⁡ j = N ∈ V
10 1 6 2 9 fvmptd3 ⊢ φ → C ⁡ N = c ∈ 0 … N 0 … M | ∑ j = 0 M c ⁡ j = N