Metamath Proof Explorer


Theorem dftermc3

Description: Alternate definition of TermCat . See also df-termc , dftermc2 . (Contributed by Zhi Wang, 20-Oct-2025)

Ref Expression
Assertion dftermc3 Could not format assertion : No typesetting found for |- TermCat = { c | ( Arrow ` c ) ~~ 1o } with typecode |-

Proof

Step Hyp Ref Expression
1 termcarweu Could not format ( c e. TermCat -> E! a a e. ( Arrow ` c ) ) : No typesetting found for |- ( c e. TermCat -> E! a a e. ( Arrow ` c ) ) with typecode |-
2 arweutermc Could not format ( E! a a e. ( Arrow ` c ) -> c e. TermCat ) : No typesetting found for |- ( E! a a e. ( Arrow ` c ) -> c e. TermCat ) with typecode |-
3 1 2 impbii Could not format ( c e. TermCat <-> E! a a e. ( Arrow ` c ) ) : No typesetting found for |- ( c e. TermCat <-> E! a a e. ( Arrow ` c ) ) with typecode |-
4 euen1b Arrow c 1 𝑜 ∃! a a Arrow c
5 3 4 bitr4i Could not format ( c e. TermCat <-> ( Arrow ` c ) ~~ 1o ) : No typesetting found for |- ( c e. TermCat <-> ( Arrow ` c ) ~~ 1o ) with typecode |-
6 5 eqabi Could not format TermCat = { c | ( Arrow ` c ) ~~ 1o } : No typesetting found for |- TermCat = { c | ( Arrow ` c ) ~~ 1o } with typecode |-