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.
The a(1) = 1 through a(8) = 16 necklace compositions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (113) (33) (115) (44)
(112) (122) (114) (133) (116)
(1111) (1112) (222) (223) (224)
(11111) (1113) (1114) (233)
(11112) (1222) (1115)
(111111) (11113) (2222)
(11122) (11114)
(11212) (11222)
(111112) (12122)
(1111111) (111113)
(111122)
(111212)
(112112)
(1111112)
(11111111)
neckQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#]}]&,Length[q]-1,1,And];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],neckQ[#]&&UnsameQ@@Length/@Split[Sort[#]]&]],{n,15}]
b(n)={((r,k,b,w)->if(!k||!r, if(r,0,(w-1)!), sum(m=0, r\k, if(!m || !bittest(b,m), self()(r-k*m, k-1, bitor(b,1<Andrew Howroyd, Aug 31 2019
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