Metamath Proof Explorer


Theorem esumel

Description: The extended sum is a limit point of the corresponding infinite group sum. (Contributed by Thierry Arnoux, 24-Mar-2017)

Ref Expression
Hypotheses esumel.1 ⊢ Ⅎ 𝑘 𝜑
esumel.2 ⊢ Ⅎ 𝑘 𝐴
esumel.3 ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 )
esumel.4 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
Assertion esumel ( 𝜑 → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) tsums ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 esumel.1 ⊢ Ⅎ 𝑘 𝜑
2 esumel.2 ⊢ Ⅎ 𝑘 𝐴
3 esumel.3 ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 )
4 esumel.4 ⊢ ( ( 𝜑 ∧ 𝑘 ∈ 𝐴 ) → 𝐵 ∈ ( 0 [,] +∞ ) )
5 4 ex ⊢ ( 𝜑 → ( 𝑘 ∈ 𝐴 → 𝐵 ∈ ( 0 [,] +∞ ) ) )
6 1 5 ralrimi ⊢ ( 𝜑 → ∀ 𝑘 ∈ 𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
7 2 esumcl ⊢ ( ( 𝐴 ∈ 𝑉 ∧ ∀ 𝑘 ∈ 𝐴 𝐵 ∈ ( 0 [,] +∞ ) ) → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
8 3 6 7 syl2anc ⊢ ( 𝜑 → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ ( 0 [,] +∞ ) )
9 snidg ⊢ ( Σ* 𝑘 ∈ 𝐴 𝐵 ∈ ( 0 [,] +∞ ) → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ { Σ* 𝑘 ∈ 𝐴 𝐵 } )
10 8 9 syl ⊢ ( 𝜑 → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ { Σ* 𝑘 ∈ 𝐴 𝐵 } )
11 eqid ⊢ ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) = ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) )
12 nfcv ⊢ Ⅎ 𝑘 ( 0 [,] +∞ )
13 eqid ⊢ ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) = ( 𝑘 ∈ 𝐴 ↦ 𝐵 )
14 1 2 12 4 13 fmptdf2 ⊢ ( 𝜑 → ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) : 𝐴 ⟶ ( 0 [,] +∞ ) )
15 inss1 ⊢ ( 𝒫 𝐴 ∩ Fin ) ⊆ 𝒫 𝐴
16 simpr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) )
17 15 16 sselid ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → 𝑥 ∈ 𝒫 𝐴 )
18 17 elpwid ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → 𝑥 ⊆ 𝐴 )
19 nfcv ⊢ Ⅎ 𝑘 𝑥
20 2 19 resmptf ⊢ ( 𝑥 ⊆ 𝐴 → ( ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ↾ 𝑥 ) = ( 𝑘 ∈ 𝑥 ↦ 𝐵 ) )
21 18 20 syl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → ( ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ↾ 𝑥 ) = ( 𝑘 ∈ 𝑥 ↦ 𝐵 ) )
22 21 eqcomd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → ( 𝑘 ∈ 𝑥 ↦ 𝐵 ) = ( ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ↾ 𝑥 ) )
23 22 oveq2d ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ) → ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) Σg ( 𝑘 ∈ 𝑥 ↦ 𝐵 ) ) = ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) Σg ( ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ↾ 𝑥 ) ) )
24 1 2 3 4 23 esumval ⊢ ( 𝜑 → Σ* 𝑘 ∈ 𝐴 𝐵 = sup ( ran ( 𝑥 ∈ ( 𝒫 𝐴 ∩ Fin ) ↦ ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) Σg ( ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ↾ 𝑥 ) ) ) , ℝ* , < ) )
25 11 3 14 24 xrge0tsmsd ⊢ ( 𝜑 → ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) tsums ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ) = { Σ* 𝑘 ∈ 𝐴 𝐵 } )
26 10 25 eleqtrrd ⊢ ( 𝜑 → Σ* 𝑘 ∈ 𝐴 𝐵 ∈ ( ( ℝ*𝑠 ↾s ( 0 [,] +∞ ) ) tsums ( 𝑘 ∈ 𝐴 ↦ 𝐵 ) ) )