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 54: every member's order is a multiple of it, and the members attaining it — the stem groups — are marked ◆.
142 groups of the catalog are in this class; the 135 with an abelian direct factor are hidden.
| group | order | × stem | |
|---|---|---|---|
| #272 | 54 | ×1 | ◆ stem |
| #1084 | 108 | ×2 | |
| #4208 | 162 | ×3 | |
| #6180 | 216 | ×4 | |
| #66410 | 324 | ×6 | |
| #88386 | 432 | ×8 | |
| #92319 | 486 | ×9 |
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.