A164403 Number of binary strings of length n with no substrings equal to 0010 or 1001

14, 25, 45, 80, 143, 255, 455, 812, 1449, 2586, 4615, 8236, 14698, 26230, 46810, 83537, 149080, 266048, 474789, 847308, 1512105, 2698501, 4815742, 8594168, 15337143, 27370649, 48845631, 87169861, 155563241, 277617994, 495436776, 884155942

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 (2,0,-1,0,1).

Formula

G.f.: x^4*(14-3*x-5*x^2+4*x^3+8*x^4)/(1-2*x+x^3-x^5). - R. J. Mathar, Nov 30 2011

Mathematica

LinearRecurrence[{2, 0, -1, 0, 1}, {14, 25, 45, 80, 143}, 50] (* G. C. Greubel, Sep 19 2017 *)

Prog

(PARI) x='x+O('x^50); Vec(x^4*(14-3*x-5*x^2+4*x^3+8*x^4)/(1-2*x+x^3-x^5)) \\ G. C. Greubel, Sep 19 2017

Crossrefs

Sequence in context: A020227 A032608 A341171 * A164398 A174519 A079505

Adjacent sequences: A164400 A164401 A164402 * A164404 A164405 A164406

Keyword

nonn

Author

R. H. Hardin, Aug 14 2009

Status

approved