Metamath Proof Explorer


Theorem fcdmnn0suppg

Description: Version of fcdmnn0supp avoiding ax-rep by assuming F is a set rather than its domain I . (Contributed by SN, 5-Aug-2024)

Ref Expression
Assertion fcdmnn0suppg ( ( 𝐹 ∈ 𝑉 ∧ 𝐹 : 𝐼 ⟶ ℕ0 ) → ( 𝐹 supp 0 ) = ( ◡ 𝐹 “ ℕ ) )

Proof

Step Hyp Ref Expression
1 c0ex ⊢ 0 ∈ V
2 fsuppeqg ⊢ ( ( 𝐹 ∈ 𝑉 ∧ 0 ∈ V ) → ( 𝐹 : 𝐼 ⟶ ℕ0 → ( 𝐹 supp 0 ) = ( ◡ 𝐹 “ ( ℕ0 ∖ { 0 } ) ) ) )
3 1 2 mpan2 ⊢ ( 𝐹 ∈ 𝑉 → ( 𝐹 : 𝐼 ⟶ ℕ0 → ( 𝐹 supp 0 ) = ( ◡ 𝐹 “ ( ℕ0 ∖ { 0 } ) ) ) )
4 3 imp ⊢ ( ( 𝐹 ∈ 𝑉 ∧ 𝐹 : 𝐼 ⟶ ℕ0 ) → ( 𝐹 supp 0 ) = ( ◡ 𝐹 “ ( ℕ0 ∖ { 0 } ) ) )
5 dfn2 ⊢ ℕ = ( ℕ0 ∖ { 0 } )
6 5 imaeq2i ⊢ ( ◡ 𝐹 “ ℕ ) = ( ◡ 𝐹 “ ( ℕ0 ∖ { 0 } ) )
7 4 6 eqtr4di ⊢ ( ( 𝐹 ∈ 𝑉 ∧ 𝐹 : 𝐼 ⟶ ℕ0 ) → ( 𝐹 supp 0 ) = ( ◡ 𝐹 “ ℕ ) )