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 A328743 #10 Nov 03 2019 15:51:05
%S A328743 1,1,0,1,2,10,26,102,336,1225,4352,15934,58190,215250,798720,2983136,
%T A328743 11184128,42109450,159070352,602809326,2290640486,8726307432,
%U A328743 33318502400,127479700198,488671717040,1876500180280,7217306664960,27799998938929,107228560958610,414124108294450
%N A328743 Number of n-bead necklace structures which are not self-equivalent under a nonzero rotation using a maximum of four different colored beads.
%C A328743 Permuting the colors does not change the structure.
%H A328743 Andrew Howroyd, <a href="/A328743/b328743.txt">Table of n, a(n) for n = 0..200</a>
%F A328743 a(n) = Sum_{k=1..4} A327693(n, k) for n > 0.
%F A328743 a(p) = A056300(p) for prime p >= 5.
%Y A328743 Cf. A056292, A056300, A327693, A328741.
%K A328743 nonn
%O A328743 0,5
%A A328743 _Andrew Howroyd_, Oct 26 2019