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A164417
Number of binary strings of length n with no substrings equal to 0000, 0010, or 0100.
2
1, 2, 4, 8, 13, 22, 39, 70, 124, 217, 381, 672, 1186, 2090, 3680, 6482, 11422, 20127, 35461, 62474, 110069, 193930, 341683, 601999, 1060637, 1868700, 3292407, 5800790, 10220220, 18006665, 31725356, 55895881, 98481140, 173510709, 305702860, 538607921, 948955781
OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..2000 (first 500 terms from R. H. Hardin)
FORMULA
G.f. -(x+1)*(x^5+x^4-x^3-x^2-1)/(x^7+x^6-x^5-x^4-x^2-x+1). - R. J. Mathar, Nov 30 2011
CROSSREFS
Sequence in context: A164415 A233274 A336980 * A258600 A227232 A164408
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
Edited by Alois P. Heinz, Oct 22 2017
STATUS
approved