Metamath Proof Explorer


Theorem 1arympt1

Description: A unary (endo)function in maps-to notation. (Contributed by AV, 16-May-2024)

Ref Expression
Hypothesis 1arympt1.f ⊢ F = x ∈ X 0 ⟼ A ⁡ x ⁡ 0
Assertion 1arympt1 ⊢ X ∈ V ∧ A : X ⟶ X → F ∈ 1 -aryF X

Proof

Step Hyp Ref Expression
1 1arympt1.f ⊢ F = x ∈ X 0 ⟼ A ⁡ x ⁡ 0
2 eqid ⊢ X 0 = X 0
3 id ⊢ x ∈ X 0 → x ∈ X 0
4 c0ex ⊢ 0 ∈ V
5 4 snid ⊢ 0 ∈ 0
6 5 a1i ⊢ x ∈ X 0 → 0 ∈ 0
7 2 3 6 mapfvd ⊢ x ∈ X 0 → x ⁡ 0 ∈ X
8 ffvelcdm ⊢ A : X ⟶ X ∧ x ⁡ 0 ∈ X → A ⁡ x ⁡ 0 ∈ X
9 7 8 sylan2 ⊢ A : X ⟶ X ∧ x ∈ X 0 → A ⁡ x ⁡ 0 ∈ X
10 9 1 fmptd ⊢ A : X ⟶ X → F : X 0 ⟶ X
11 1aryfvalel ⊢ X ∈ V → F ∈ 1 -aryF X ↔ F : X 0 ⟶ X
12 10 11 imbitrrid ⊢ X ∈ V → A : X ⟶ X → F ∈ 1 -aryF X
13 12 imp ⊢ X ∈ V ∧ A : X ⟶ X → F ∈ 1 -aryF X