OFFSET
1,1
COMMENTS
A necklace is a finite sequence that is lexicographically minimal among all of its cyclic rotations.
EXAMPLE
The sequence of terms together with their binary expansions begins:
6: (1,1,0)
10: (1,0,1,0)
12: (1,1,0,0)
13: (1,1,0,1)
14: (1,1,1,0)
18: (1,0,0,1,0)
20: (1,0,1,0,0)
22: (1,0,1,1,0)
24: (1,1,0,0,0)
25: (1,1,0,0,1)
26: (1,1,0,1,0)
27: (1,1,0,1,1)
28: (1,1,1,0,0)
29: (1,1,1,0,1)
30: (1,1,1,1,0)
34: (1,0,0,0,1,0)
36: (1,0,0,1,0,0)
38: (1,0,0,1,1,0)
40: (1,0,1,0,0,0)
41: (1,0,1,0,0,1)
MATHEMATICA
neckQ[q_]:=Array[OrderedQ[{q, RotateRight[q, #]}]&, Length[q]-1, 1, And];
Select[Range[2, 100], !neckQ[Rest[IntegerDigits[#, 2]]]&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Nov 15 2019
STATUS
approved