Groups whose commutator structure agrees: there are isomorphisms G/Z(G) → H/Z(H) and G′ → H′ carrying one commutator map to the other. The class spans orders — G × A is isoclinic to G for every abelian A.
Stem order 10: every member's order is a multiple of it, and the members attaining it — the stem groups — are marked ◆.
2,458 groups of the catalog are in this class; the 2,450 with an abelian direct factor are hidden.
| group | order | × stem | |
|---|---|---|---|
| D5 | 10 | ×1 | ◆ stem |
| Dic5 | 20 | ×2 | |
| #168 | 40 | ×4 | |
| #672 | 80 | ×8 | |
| #3926 | 160 | ×16 | |
| #64663 | 320 | ×32 | |
| #10597919 | 640 | ×64 | |
| #11985825 | 1,280 | ×128 |
The class itself is infinite — G × A is isoclinic to G for every abelian A, and there are abelian groups of every order — so a table shows the part of it the catalog names, never the whole.