Metamath Proof Explorer


Theorem prstcnidlem

Description: Lemma for prstcnid and prstchomval . (Contributed by Zhi Wang, 20-Sep-2024) (New usage is discouraged.)

Ref Expression
Hypotheses prstcnid.c ⊢ φ → C = ProsetToCat ⁡ K
prstcnid.k ⊢ φ → K ∈ Proset
prstcnid.e ⊢ E = Slot E ⁡ ndx
prstcnid.no ⊢ E ⁡ ndx ≠ comp ⁡ ndx
Assertion prstcnidlem ⊢ φ → E ⁡ C = E ⁡ K sSet Hom ⁡ ndx ≤ K × 1 𝑜

Proof

Step Hyp Ref Expression
1 prstcnid.c ⊢ φ → C = ProsetToCat ⁡ K
2 prstcnid.k ⊢ φ → K ∈ Proset
3 prstcnid.e ⊢ E = Slot E ⁡ ndx
4 prstcnid.no ⊢ E ⁡ ndx ≠ comp ⁡ ndx
5 1 2 prstcval ⊢ φ → C = K sSet Hom ⁡ ndx ≤ K × 1 𝑜 sSet comp ⁡ ndx ∅
6 5 fveq2d ⊢ φ → E ⁡ C = E ⁡ K sSet Hom ⁡ ndx ≤ K × 1 𝑜 sSet comp ⁡ ndx ∅
7 3 4 setsnid ⊢ E ⁡ K sSet Hom ⁡ ndx ≤ K × 1 𝑜 = E ⁡ K sSet Hom ⁡ ndx ≤ K × 1 𝑜 sSet comp ⁡ ndx ∅
8 6 7 eqtr4di ⊢ φ → E ⁡ C = E ⁡ K sSet Hom ⁡ ndx ≤ K × 1 𝑜