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A361871
The smallest order of a non-abelian group with an element of order n.
0
6, 6, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120
OFFSET
1,1
FORMULA
a(n) = 2*n for n >= 3.
Proof: By Lagrange's theorem in group theory we have that n divides a(n) for all n. A group of order n and with an element of order n is the cyclic group of order n, hence being abelian. On the other hand, the dihedral group D_{2n} is non-abelian for n >= 3 and contains an element of order n. - Jianing Song, Aug 11 2023
CROSSREFS
Essentially the same as A163300, A103517, A051755.
Sequence in context: A135357 A322346 A332559 * A179415 A179409 A186983
KEYWORD
nonn,easy
AUTHOR
Yue Yu, Apr 01 2023
STATUS
approved