Metamath Proof Explorer


Theorem esumid

Description: Identify the extended sum as any limit points of the infinite sum. (Contributed by Thierry Arnoux, 9-May-2017)

Ref Expression
Hypotheses esumid.p ⊢ Ⅎ k φ
esumid.0 ⊢ Ⅎ _ k A
esumid.1 ⊢ φ → A ∈ V
esumid.2 ⊢ φ ∧ k ∈ A → B ∈ 0 +∞
esumid.3 ⊢ φ → C ∈ ℝ 𝑠 * ↾ 𝑠 0 +∞ tsums k ∈ A ⟼ B
Assertion esumid ⊢ φ → ∑ * k ∈ A B = C

Proof

Step Hyp Ref Expression
1 esumid.p ⊢ Ⅎ k φ
2 esumid.0 ⊢ Ⅎ _ k A
3 esumid.1 ⊢ φ → A ∈ V
4 esumid.2 ⊢ φ ∧ k ∈ A → B ∈ 0 +∞
5 esumid.3 ⊢ φ → C ∈ ℝ 𝑠 * ↾ 𝑠 0 +∞ tsums k ∈ A ⟼ B
6 df-esum ⊢ ∑ * k ∈ A B = ⋃ ℝ 𝑠 * ↾ 𝑠 0 +∞ tsums k ∈ A ⟼ B
7 eqid ⊢ ℝ 𝑠 * ↾ 𝑠 0 +∞ = ℝ 𝑠 * ↾ 𝑠 0 +∞
8 nfcv ⊢ Ⅎ _ k 0 +∞
9 eqid ⊢ k ∈ A ⟼ B = k ∈ A ⟼ B
10 1 2 8 4 9 fmptdf2 ⊢ φ → k ∈ A ⟼ B : A ⟶ 0 +∞
11 7 3 10 5 xrge0tsmseq ⊢ φ → C = ⋃ ℝ 𝑠 * ↾ 𝑠 0 +∞ tsums k ∈ A ⟼ B
12 6 11 eqtr4id ⊢ φ → ∑ * k ∈ A B = C