A234005 Number of binary words of length n avoiding the subword given by the binary expansion of n.

1, 1, 3, 5, 12, 21, 33, 81, 177, 338, 667, 1178, 2031, 4105, 6872, 20569, 42744, 84457, 167863, 315633, 590081, 1325032, 2366125, 4408350, 8146016, 16474904, 30266484, 67320433, 112454976, 230099960, 417825921, 1333610936, 2714234540, 5411487988, 10800172911

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Example

a(0) = 1: the empty word.
a(1) = 1: 0.
a(2) = 3: 00, 01, 11.
a(3) = 5: 000, 001, 010, 100, 101.
a(4) = 12: 0000, 0001, 0010, 0011, 0101, 0110, 0111, 1010, 1011, 1101, 1110, 1111.

Crossrefs

Main diagonal of A209972.

Column k=0 of A233940.

Sequence in context: A309702 A358369 A143360 * A263346 A034763 A183921

Adjacent sequences: A234002 A234003 A234004 * A234006 A234007 A234008

Keyword

nonn

Author

Alois P. Heinz, Dec 18 2013

Status

approved