Description: The relation "is isomorphic to" for groups. (Contributed by Stefan O'Rear, 25-Jan-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | brgic | |- ( R ~=g S <-> ( R GrpIso S ) =/= (/) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-gic | |- ~=g = ( `' GrpIso " ( _V \ 1o ) ) | |
| 2 | gimfn | |- GrpIso Fn ( Grp X. Grp ) | |
| 3 | 1 2 | brwitnlem | |- ( R ~=g S <-> ( R GrpIso S ) =/= (/) ) |