Metamath Proof Explorer


Theorem parhomcl

Description: All hom-sets of the parallel-arrow construction lie in its arrow carrier. (Contributed by Zhi Wang, 14-Sep-2026) (Revised by Zhi Wang, 16-Sep-2026)

Ref Expression
Hypotheses parhomval.h ⊢ H = x ∈ B , y ∈ B ⟼ if x = y J if x = X ∧ y = Y S ∅
parhomssun.k ⊢ K = S ∪ J
parhomcl.f ⊢ φ → F ∈ U H V
Assertion parhomcl ⊢ φ → F ∈ K

Proof

Step Hyp Ref Expression
1 parhomval.h ⊢ H = x ∈ B , y ∈ B ⟼ if x = y J if x = X ∧ y = Y S ∅
2 parhomssun.k ⊢ K = S ∪ J
3 parhomcl.f ⊢ φ → F ∈ U H V
4 1 2 parhomssun ⊢ U H V ⊆ K
5 4 3 sselid ⊢ φ → F ∈ K