Metamath Proof Explorer


Theorem eulerpartlemelr

Description: Lemma for eulerpart . (Contributed by Thierry Arnoux, 8-Aug-2018)

Ref Expression
Hypotheses eulerpartlems.r ⊢ 𝑅 = { 𝑓 ∣ ( ◡ 𝑓 “ ℕ ) ∈ Fin }
eulerpartlems.s ⊢ 𝑆 = ( 𝑓 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) ↦ Σ 𝑘 ∈ ℕ ( ( 𝑓 ‘ 𝑘 ) · 𝑘 ) )
Assertion eulerpartlemelr ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → ( 𝐴 : ℕ ⟶ ℕ0 ∧ ( ◡ 𝐴 “ ℕ ) ∈ Fin ) )

Proof

Step Hyp Ref Expression
1 eulerpartlems.r ⊢ 𝑅 = { 𝑓 ∣ ( ◡ 𝑓 “ ℕ ) ∈ Fin }
2 eulerpartlems.s ⊢ 𝑆 = ( 𝑓 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) ↦ Σ 𝑘 ∈ ℕ ( ( 𝑓 ‘ 𝑘 ) · 𝑘 ) )
3 inss1 ⊢ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) ⊆ ( ℕ0 ↑m ℕ )
4 3 sseli ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → 𝐴 ∈ ( ℕ0 ↑m ℕ ) )
5 elmapi ⊢ ( 𝐴 ∈ ( ℕ0 ↑m ℕ ) → 𝐴 : ℕ ⟶ ℕ0 )
6 4 5 syl ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → 𝐴 : ℕ ⟶ ℕ0 )
7 inss2 ⊢ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) ⊆ 𝑅
8 7 sseli ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → 𝐴 ∈ 𝑅 )
9 cnveq ⊢ ( 𝑓 = 𝐴 → ◡ 𝑓 = ◡ 𝐴 )
10 9 imaeq1d ⊢ ( 𝑓 = 𝐴 → ( ◡ 𝑓 “ ℕ ) = ( ◡ 𝐴 “ ℕ ) )
11 10 eleq1d ⊢ ( 𝑓 = 𝐴 → ( ( ◡ 𝑓 “ ℕ ) ∈ Fin ↔ ( ◡ 𝐴 “ ℕ ) ∈ Fin ) )
12 11 1 elab2g ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → ( 𝐴 ∈ 𝑅 ↔ ( ◡ 𝐴 “ ℕ ) ∈ Fin ) )
13 8 12 mpbid ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → ( ◡ 𝐴 “ ℕ ) ∈ Fin )
14 6 13 jca ⊢ ( 𝐴 ∈ ( ( ℕ0 ↑m ℕ ) ∩ 𝑅 ) → ( 𝐴 : ℕ ⟶ ℕ0 ∧ ( ◡ 𝐴 “ ℕ ) ∈ Fin ) )