Metamath Proof Explorer


Theorem findfvcl

Description: Please add description here. (Contributed by Jeff Hoffman, 12-Feb-2008)

Ref Expression
Hypotheses findfvcl.1 ⊢ ( 𝜑 → ( 𝐹 ‘ ∅ ) ∈ 𝑃 )
findfvcl.2 ⊢ ( 𝑦 ∈ ω → ( 𝜑 → ( ( 𝐹 ‘ 𝑦 ) ∈ 𝑃 → ( 𝐹 ‘ suc 𝑦 ) ∈ 𝑃 ) ) )
Assertion findfvcl ( 𝐴 ∈ ω → ( 𝜑 → ( 𝐹 ‘ 𝐴 ) ∈ 𝑃 ) )

Proof

Step Hyp Ref Expression
1 findfvcl.1 ⊢ ( 𝜑 → ( 𝐹 ‘ ∅ ) ∈ 𝑃 )
2 findfvcl.2 ⊢ ( 𝑦 ∈ ω → ( 𝜑 → ( ( 𝐹 ‘ 𝑦 ) ∈ 𝑃 → ( 𝐹 ‘ suc 𝑦 ) ∈ 𝑃 ) ) )
3 fveleq ⊢ ( 𝑥 = ∅ → ( ( 𝜑 → ( 𝐹 ‘ 𝑥 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹 ‘ ∅ ) ∈ 𝑃 ) ) )
4 fveleq ⊢ ( 𝑥 = 𝑦 → ( ( 𝜑 → ( 𝐹 ‘ 𝑥 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹 ‘ 𝑦 ) ∈ 𝑃 ) ) )
5 fveleq ⊢ ( 𝑥 = suc 𝑦 → ( ( 𝜑 → ( 𝐹 ‘ 𝑥 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹 ‘ suc 𝑦 ) ∈ 𝑃 ) ) )
6 fveleq ⊢ ( 𝑥 = 𝐴 → ( ( 𝜑 → ( 𝐹 ‘ 𝑥 ) ∈ 𝑃 ) ↔ ( 𝜑 → ( 𝐹 ‘ 𝐴 ) ∈ 𝑃 ) ) )
7 2 a2d ⊢ ( 𝑦 ∈ ω → ( ( 𝜑 → ( 𝐹 ‘ 𝑦 ) ∈ 𝑃 ) → ( 𝜑 → ( 𝐹 ‘ suc 𝑦 ) ∈ 𝑃 ) ) )
8 3 4 5 6 1 7 finds ⊢ ( 𝐴 ∈ ω → ( 𝜑 → ( 𝐹 ‘ 𝐴 ) ∈ 𝑃 ) )