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A164415
Number of binary strings of length n with no substrings equal to 0000, 0001, or 1100.
2
1, 2, 4, 8, 13, 22, 38, 65, 112, 193, 332, 572, 985, 1696, 2921, 5030, 8662, 14917, 25688, 44237, 76180, 131188, 225917, 389048, 669973, 1153750, 1986854, 3421529, 5892160, 10146793, 17473628, 30091052, 51819313, 89237200, 153673937, 264639398, 455731222
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^2-1)/(x^4-x^3-x^2-x+1). - R. J. Mathar, Nov 28 2011
CROSSREFS
Sequence in context: A074467 A018066 A164509 * A233274 A336980 A164417
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
Edited by Alois P. Heinz, Oct 12 2017
STATUS
approved