A164473 Number of binary strings of length n with no substrings equal to 0001 0101 or 1011.

13, 21, 34, 53, 82, 128, 198, 305, 471, 726, 1117, 1720, 2648, 4074, 6269, 9647, 14842, 22835, 35134, 54054, 83162, 127947, 196847, 302848, 465933, 716838, 1102852, 1696736, 2610425, 4016129, 6178802, 9506069, 14625054, 22500596, 34617094

Offset

4,1

Links

R. H. Hardin, Table of n, a(n) for n=4..500

Index entries for linear recurrences with constant coefficients, signature (2,-1,1,-1,0,1,-1).

Formula

G.f.: -x^4*(-13+5*x-5*x^2+7*x^3-2*x^4-4*x^5+8*x^6) / ( (x-1)*(x^6+x^3+x-1) ). - R. J. Mathar, Jan 19 2011

Crossrefs

Sequence in context: A057200 A164454 A164426 * A164481 A164433 A164479

Adjacent sequences: A164470 A164471 A164472 * A164474 A164475 A164476

Keyword

nonn,easy

Author

R. H. Hardin, Aug 14 2009

Status

approved