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 A328039 #12 Oct 25 2019 16:34:28 %S A328039 0,0,0,1,2,10,32,129,468,1806,6780,25917,98056,372919,1414548,5375974, %T A328039 20432480,77773845,296350460,1130919576,4321818986,16540888897, %U A328039 63399449652,243357204415,935428588930,3600514267686,13876474860110,53546226302319,206864885150216 %N A328039 Number of primitive (period n) n-bead bracelet structures which are not periodic palindromes using exactly four different colored beads. %C A328039 Permuting the colors of the beads will not change the structure. %H A328039 Andrew Howroyd, <a href="/A328039/b328039.txt">Table of n, a(n) for n = 1..200</a> %F A328039 a(n) = A056368(n) - A056521(n). %Y A328039 Column 4 of A309784. %Y A328039 Cf. A056368, A056521, A328035, A328038, A328658. %K A328039 nonn %O A328039 1,5 %A A328039 _Andrew Howroyd_, Oct 02 2019