Also called  C7×C3.

C21 is Abelian, and is a direct product of two smaller groups.


Order of group21
GAP identifier21,2
Presentation< k | k21 >
Orders of elements1 of 1, 2*1 of 3, 6*1 of 7, 12*1 of 21
Derived subgroup1
Automorphism groupC6×C2
Inner automorphism group1
"Out" (quotient of above)C6×C2
Schur multiplier1

Permutation Diagrams

Not transitive.

Not transitive.

Sharply 1-transitive
on 21 points, even.

Cayley Graphs

Index to regular maps