A164458 Number of binary strings of length n with no substrings equal to 0001 0011 or 1011.

13, 21, 32, 47, 68, 96, 134, 185, 253, 344, 465, 626, 840, 1124, 1501, 2001, 2664, 3543, 4708, 6252, 8298, 11009, 14601, 19360, 25665, 34018, 45084, 59744, 79165, 104893, 138976, 184127, 243940, 323176, 428142, 567193, 751397, 995416, 1318673, 1746898

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,-1,1).

Formula

G.f.: -x^4*(13-5*x-10*x^2-4*x^3+8*x^4) / ( (x^3+x^2-1)*(x-1)^2 ). - R. J. Mathar, Jan 19 2011

Mathematica

LinearRecurrence[{2, 0, -1, -1, 1}, {13, 21, 32, 47, 68}, 60] (* Harvey P. Dale, Sep 04 2019 *)

Crossrefs

Sequence in context: A050711 A282844 A020440 * A164452 A164444 A164438

Adjacent sequences: A164455 A164456 A164457 * A164459 A164460 A164461

Keyword

nonn,easy

Author

R. H. Hardin, Aug 14 2009

Status

approved