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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.

A333943 Numbers k such that the k-th composition in standard order is a reversed necklace.

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%I A333943 #4 Apr 15 2020 09:52:57
%S A333943 1,2,3,4,5,7,8,9,10,11,15,16,17,18,19,21,23,31,32,33,34,35,36,37,39,
%T A333943 41,42,43,45,47,63,64,65,66,67,68,69,71,73,74,75,77,79,81,83,85,87,91,
%U A333943 95,127,128,129,130,131,132,133,135,136,137,138,139,141,143
%N A333943 Numbers k such that the k-th composition in standard order is a reversed necklace.
%C A333943 A necklace is a finite sequence that is lexicographically minimal among all of its cyclic rotations. Reversed necklaces are different from co-necklaces (A333764).
%C A333943 A composition of n is a finite sequence of positive integers summing to n. The k-th composition in standard order (row k of A066099) is obtained by taking the set of positions of 1's in the reversed binary expansion of k, prepending 0, taking first differences, and reversing again. This gives a bijective correspondence between nonnegative integers and integer compositions.
%e A333943 The sequence together with the corresponding reversed necklaces begins:
%e A333943     1: (1)             32: (6)               69: (4,2,1)
%e A333943     2: (2)             33: (5,1)             71: (4,1,1,1)
%e A333943     3: (1,1)           34: (4,2)             73: (3,3,1)
%e A333943     4: (3)             35: (4,1,1)           74: (3,2,2)
%e A333943     5: (2,1)           36: (3,3)             75: (3,2,1,1)
%e A333943     7: (1,1,1)         37: (3,2,1)           77: (3,1,2,1)
%e A333943     8: (4)             39: (3,1,1,1)         79: (3,1,1,1,1)
%e A333943     9: (3,1)           41: (2,3,1)           81: (2,4,1)
%e A333943    10: (2,2)           42: (2,2,2)           83: (2,3,1,1)
%e A333943    11: (2,1,1)         43: (2,2,1,1)         85: (2,2,2,1)
%e A333943    15: (1,1,1,1)       45: (2,1,2,1)         87: (2,2,1,1,1)
%e A333943    16: (5)             47: (2,1,1,1,1)       91: (2,1,2,1,1)
%e A333943    17: (4,1)           63: (1,1,1,1,1,1)     95: (2,1,1,1,1,1)
%e A333943    18: (3,2)           64: (7)              127: (1,1,1,1,1,1,1)
%e A333943    19: (3,1,1)         65: (6,1)            128: (8)
%e A333943    21: (2,2,1)         66: (5,2)            129: (7,1)
%e A333943    23: (2,1,1,1)       67: (5,1,1)          130: (6,2)
%e A333943    31: (1,1,1,1,1)     68: (4,3)            131: (6,1,1)
%t A333943 stc[n_]:=Differences[Prepend[Join@@Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
%t A333943 neckQ[q_]:=Array[OrderedQ[{q,RotateRight[q,#1]}]&,Length[q]-1,1,And];
%t A333943 Select[Range[100],neckQ[Reverse[stc[#]]]&]
%Y A333943 The non-reversed version is A065609.
%Y A333943 The dual version is A328595.
%Y A333943 Binary necklaces are A000031.
%Y A333943 Necklace compositions are A008965.
%Y A333943 Necklaces covering an initial interval are A019536.
%Y A333943 Numbers whose prime signature is a necklace are A329138.
%Y A333943 Length of co-Lyndon factorization of binary expansion is A329312.
%Y A333943 Length of Lyndon factorization of reversed binary expansion is A329313.
%Y A333943 All of the following pertain to compositions in standard order (A066099):
%Y A333943 - Length is A000120.
%Y A333943 - Sum is A070939.
%Y A333943 - Runs are counted by A124767.
%Y A333943 - Rotational symmetries are counted by A138904.
%Y A333943 - Strict compositions are A233564.
%Y A333943 - Constant compositions are A272919.
%Y A333943 - Lyndon compositions are A275692.
%Y A333943 - Co-Lyndon compositions are A326774.
%Y A333943 - Aperiodic compositions are A328594.
%Y A333943 - Length of Lyndon factorization is A329312.
%Y A333943 - Rotational period is A333632.
%Y A333943 - Co-necklaces are A333764.
%Y A333943 - Length of co-Lyndon factorization is A334029.
%Y A333943 Cf. A000740, A001037, A027375, A059966, A211100, A302291, A328596, A329142, A333765, A333939, A333941.
%K A333943 nonn
%O A333943 1,2
%A A333943 _Gus Wiseman_, Apr 14 2020