A164415 Number of binary strings of length n with no substrings equal to 0000, 0001, or 1100.

1, 2, 4, 8, 13, 22, 38, 65, 112, 193, 332, 572, 985, 1696, 2921, 5030, 8662, 14917, 25688, 44237, 76180, 131188, 225917, 389048, 669973, 1153750, 1986854, 3421529, 5892160, 10146793, 17473628, 30091052, 51819313, 89237200, 153673937, 264639398, 455731222

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..2000 (first 500 terms from R. H. Hardin)

Index entries for linear recurrences with constant coefficients, signature (1, 1, 1, -1).

Formula

G.f.: -(x+1)*(x^5-x^2-1)/(x^4-x^3-x^2-x+1). - R. J. Mathar, Nov 28 2011

Crossrefs

Sequence in context: A074467 A018066 A164509 * A233274 A336980 A164417

Adjacent sequences: A164412 A164413 A164414 * A164416 A164417 A164418

Keyword

nonn,easy

Author

R. H. Hardin, Aug 14 2009

Extensions

Edited by Alois P. Heinz, Oct 12 2017

Status

approved