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 A066315 #9 Aug 28 2019 08:15:55
%S A066315 1,1,3,7,20,51,154,460,1476,4860,16544,57321,202059,720370,2593470,
%T A066315 9408000,34350506,126108252,465200332,1723341185,6408356052,
%U A066315 23911255544,89495909408,335916703284,1264114452975,4768464107355
%N A066315 Number of aperiodic bracelets (or necklaces) with n red and blue beads such that the beads switch colors when bracelet is turned over.
%H A066315 <a href="/index/Br#bracelets">Index entries for sequences related to bracelets</a>
%F A066315 Moebius transform of A006080(n+1).
%t A066315 a[n_] := Sum[MoebiusMu[n/d] A006080[d + 1], {d, Divisors[n]}];
%t A066315 Array[a, 26] (* _Jean-François Alcover_, Aug 28 2019 *)
%K A066315 nonn
%O A066315 1,3
%A A066315 _Christian G. Bower_, Dec 13 2001