A164467 Number of binary strings of length n with no substrings equal to 0001 0100 or 1101.

13, 20, 31, 48, 74, 113, 172, 261, 396, 600, 909, 1376, 2083, 3152, 4770, 7217, 10920, 16521, 24996, 37816, 57213, 86556, 130951, 198112, 299722, 453441, 686004, 1037837, 1570124, 2375400, 3593693, 5436808, 8225227, 12443744, 18825858

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,-2,2,-1).

Formula

G.f.: -x^4*(-13+6*x+9*x^2-12*x^3+8*x^4) / ( (x-1)*(x^4-x^3+x^2+x-1) ). - R. J. Mathar, Jan 19 2011

Crossrefs

Sequence in context: A164468 A164489 A164464 * A164505 A164484 A164502

Adjacent sequences: A164464 A164465 A164466 * A164468 A164469 A164470

Keyword

nonn,easy

Author

R. H. Hardin, Aug 14 2009

Status

approved