Description: A class is a set iff its transitive closure is a set, assuming Transitive Containment. (Contributed by Matthew House, 6-Apr-2026)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ttcexbi | Could not format assertion : No typesetting found for |- ( A e. _V <-> TC+ A e. _V ) with typecode |- |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ttcexg | Could not format ( A e. _V -> TC+ A e. _V ) : No typesetting found for |- ( A e. _V -> TC+ A e. _V ) with typecode |- | |
| 2 | ttcexrg | Could not format ( TC+ A e. _V -> A e. _V ) : No typesetting found for |- ( TC+ A e. _V -> A e. _V ) with typecode |- | |
| 3 | 1 2 | impbii | Could not format ( A e. _V <-> TC+ A e. _V ) : No typesetting found for |- ( A e. _V <-> TC+ A e. _V ) with typecode |- |