This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A361871 #15 Aug 11 2023 09:53:26
%S A361871 6,6,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,
%T A361871 50,52,54,56,58,60,62,64,66,68,70,72,74,76,78,80,82,84,86,88,90,92,94,
%U A361871 96,98,100,102,104,106,108,110,112,114,116,118,120
%N A361871 The smallest order of a non-abelian group with an element of order n.
%H A361871 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lagrange%27s_theorem_(group_theory)">Lagrange's theorem (group theory)</a>
%F A361871 a(n) = 2*n for n >= 3.
%F A361871 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
%Y A361871 Essentially the same as A163300, A103517, A051755.
%K A361871 nonn,easy
%O A361871 1,1
%A A361871 _Yue Yu_, Apr 01 2023