A164447 Number of binary strings of length n with no substrings equal to 0001 0010 or 0110.

13, 21, 33, 54, 88, 144, 233, 377, 609, 986, 1596, 2584, 4181, 6765, 10945, 17710, 28656, 46368, 75025, 121393, 196417, 317810, 514228, 832040, 1346269, 2178309, 3524577, 5702886, 9227464, 14930352, 24157817, 39088169, 63245985, 102334154

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

Formula

G.f.: -x^4*(-13+5*x+9*x^2-14*x^3+4*x^4+8*x^5) / ( (x-1)*(1+x)*(x^2-x+1)*(x^2+x-1) ). - R. J. Mathar, Jan 19 2011

Crossrefs

Sequence in context: A164436 A164498 A164485 * A057200 A164454 A164426

Adjacent sequences: A164444 A164445 A164446 * A164448 A164449 A164450

Keyword

nonn,easy

Author

R. H. Hardin, Aug 14 2009

Status

approved