 These are related by an outer automorphism, which can be represented by rotation through π/"n", half the minimal rotation in the dihedral group.Another example are the Sylow p-subgroups of "GL"2("F""q"), where "p" and "q" are primes ≥ 3 and "p" ≡ 1 (mod "q") , which are all abelian.The order of "GL"2("F""q") is ("q"2 − 1)("q"2 − "q") = ("q")("q" + 1)("q" − 1)2.