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A164500
Number of binary strings of length n with no substrings equal to 0010 1001 or 1010.
1
13, 21, 36, 60, 100, 168, 281, 470, 787, 1317, 2204, 3689, 6174, 10333, 17294, 28944, 48442, 81075, 135691, 227099, 380084, 636127, 1064653, 1781855, 2982199, 4991153, 8353436, 13980716, 23398805, 39161376, 65542380, 109694909, 183590725
OFFSET
4,1
FORMULA
G.f.: -x^4*(13-5*x+7*x^2-4*x^3+8*x^4) / ( -1+2*x-x^2+x^3-x^4+x^5 ). - R. J. Mathar, Jan 19 2011
CROSSREFS
Sequence in context: A164477 A164423 A164422 * A164430 A045679 A137194
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
STATUS
approved