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A218869 Triangle read by rows: T(n,k) = number of aperiodic binary sequences of length n with curling number k (1 <= k <= n).

%I A218869 #31 Aug 02 2014 06:21:33
%S A218869 2,2,0,4,2,0,6,4,2,0,12,12,4,2,0,20,20,8,4,2,0,40,52,20,8,4,2,0,74,
%T A218869 100,36,16,8,4,2,0,148,214,76,36,16,8,4,2,0,286,414,160,68,32,16,8,4,
%U A218869 2,0,572,876,328,140,68,32,16,8,4,2,0,1124,1722,640,276,132,64,32,16,8,4,2,0
%N A218869 Triangle read by rows: T(n,k) = number of aperiodic binary sequences of length n with curling number k (1 <= k <= n).
%C A218869 S is aperiodic if it is not of the form S = T^m with m > 1.
%C A218869 Row sums are A027375. First column is A122536.
%C A218869 It appears that reversed rows converge to A155559. - _Omar E. Pol_, Nov 20 2012
%H A218869 B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="http://arxiv.org/abs/1212.6102">On Curling Numbers of Integer Sequences</a>, arXiv:1212.6102, Dec 25 2012.
%H A218869 B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Sloane/sloane3.html">On Curling Numbers of Integer Sequences</a>, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.
%H A218869 John P. Linderman, <a href="/A218869/a218869.txt">Rows 1 through 64</a> (Rows 1 through 36 were computed by _N. J. A. Sloane_)
%H A218869 <a href="/index/Cu#curling_numbers">Index entries for sequences related to curling numbers</a>
%e A218869 Triangle begins:
%e A218869 2,
%e A218869 2, 0,
%e A218869 4, 2, 0,
%e A218869 6, 4, 2, 0,
%e A218869 12, 12, 4, 2, 0,
%e A218869 20, 20, 8, 4, 2, 0,
%e A218869 40, 52, 20, 8, 4, 2, 0,
%e A218869 74, 100, 36, 16, 8, 4, 2, 0,
%e A218869 148, 214, 76, 36, 16, 8, 4, 2, 0,
%e A218869 286, 414, 160, 68, 32, 16, 8, 4, 2, 0,
%e A218869 572, 876, 328, 140, 68, 32, 16, 8, 4, 2, 0,
%e A218869 ...
%Y A218869 Cf. A216955, A122536, A027375, A218870.
%K A218869 nonn,tabl
%O A218869 1,1
%A A218869 _N. J. A. Sloane_, Nov 07 2012