A218875 Triangle read by rows: T(n,k) (1 <= k <= n) = number of robust primitive binary sequences of length n and curling number k.

2, 2, 0, 4, 2, 0, 6, 4, 2, 0, 10, 12, 4, 2, 0, 20, 20, 8, 4, 2, 0, 36, 52, 20, 8, 4, 2, 0, 72, 98, 36, 16, 8, 4, 2, 0, 142, 214, 76, 36, 16, 8, 4, 2, 0, 280, 414, 160, 68, 32, 16, 8, 4, 2, 0, 560, 870, 326, 140, 68, 32, 16, 8, 4, 2, 0, 1114, 1720, 640, 276, 132, 64, 32, 16, 8, 4, 2, 0

Offset: 1

Author

N. J. A. Sloane, Nov 15 2012

Keywords

• nonn
• tabl

Examples

			Triangle begins:
[2],
[2, 0],
[4, 2, 0],
[6, 4, 2, 0],
[10, 12, 4, 2, 0],
[20, 20, 8, 4, 2, 0],
[36, 52, 20, 8, 4, 2, 0],
[72, 98, 36, 16, 8, 4, 2, 0],
[142, 214, 76, 36, 16, 8, 4, 2, 0],
[280, 414, 160, 68, 32, 16, 8, 4, 2, 0],
...
		

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, First 36 rows of table
• Index entries for sequences related to curling numbers

Crossrefs

Cf. A216955, A218869, A218876. First column is A216958.

Formula

The triangle in A218869 is the sum of triangles A218875 and A218876.