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A218870
Triangle read by rows: T(n,k) = number of aperiodic binary sequences of length n with curling number <= k (1 <= k <= n).
3
2, 2, 2, 4, 6, 6, 6, 10, 12, 12, 12, 24, 28, 30, 30, 20, 40, 48, 52, 54, 54, 40, 92, 112, 120, 124, 126, 126, 74, 174, 210, 226, 234, 238, 240, 240, 148, 362, 438, 474, 490, 498, 502, 504, 504, 286, 700, 860, 928, 960, 976, 984, 988, 990, 990, 572, 1448, 1776, 1916, 1984, 2016, 2032, 2040, 2044, 2046, 2046
OFFSET
1,1
COMMENTS
S is aperiodic if it is not of the form S = T^m with m > 1.
Rows are partial sums of rows of A218869.
Final entries in rows form A027375. First column is A122536.
LINKS
B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, arXiv:1212.6102, Dec 25 2012.
B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.
N. J. A. Sloane, Rows 1 through 36
EXAMPLE
Triangle begins:
[2]
[2, 2]
[4, 6, 6]
[6, 10, 12, 12]
[12, 24, 28, 30, 30]
[20, 40, 48, 52, 54, 54]
[40, 92, 112, 120, 124, 126, 126]
[74, 174, 210, 226, 234, 238, 240, 240]
[148, 362, 438, 474, 490, 498, 502, 504, 504]
[286, 700, 860, 928, 960, 976, 984, 988, 990, 990]
[572, 1448, 1776, 1916, 1984, 2016, 2032, 2040, 2044, 2046, 2046]
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Nov 07 2012
STATUS
approved