Finite Group Databasebeta

Isoclinism class

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 21: every member's order is a multiple of it, and the members attaining it — the stem groups — are marked ◆.

1,158 groups of the catalog are in this class; the 1,153 with an abelian direct factor are hidden.

grouporder× stem
ΓL(1,𝔽8)21×1◆ stem
C7⋊C963×3
C7⋊C27189×9
C7⋊C81567×27
C7⋊C2431,701×81

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.