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A164476
Number of binary strings of length n with no substrings equal to 0001, 0110, or 0111.
1
1, 2, 4, 8, 13, 20, 30, 43, 61, 85, 117, 160, 217, 293, 394, 528, 706, 942, 1255, 1670, 2220, 2949, 3915, 5195, 6891, 9138, 12115, 16059, 21284, 28206, 37376, 49524, 65617, 86936, 115178, 152591, 202153, 267809, 354785, 470004, 622637, 824833, 1092686, 1447516
OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..2500 (first 500 terms from R. H. Hardin)
FORMULA
G.f.: (x^5-x^3-1)/((x^3+x^2-1)*(x-1)^2). - R. J. Mathar, Jan 19 2011
MATHEMATICA
LinearRecurrence[{2, 0, -1, -1, 1}, {1, 2, 4, 8, 13, 20}, 44] (* Harvey P. Dale, Apr 13 2016; amended for offset 0 by Georg Fischer, Apr 03 2019 *)
PROG
(PARI) x='x+O('x^44); Vec((x^5-x^3-1)/((x^3+x^2-1)*(x-1)^2)) \\ Georg Fischer, Apr 03 2019
CROSSREFS
Sequence in context: A349216 A247587 A061866 * A164466 A164487 A130840
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
Edited by Alois P. Heinz, Oct 27 2017
STATUS
approved