

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
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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

Table of n, a(n) for n=1..66.
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
Index entries for sequences related to curling numbers


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

Cf. A216955, A122536, A027375, A218869.
Sequence in context: A170887 A103265 A008238 * A264869 A096575 A002722
Adjacent sequences: A218867 A218868 A218869 * A218871 A218872 A218873


KEYWORD

nonn,tabl


AUTHOR

N. J. A. Sloane, Nov 07 2012


STATUS

approved



