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A164507
Number of binary strings of length n with no substrings equal to 0011, 0110, or 1100.
1
1, 2, 4, 8, 13, 22, 37, 63, 106, 180, 304, 515, 871, 1475, 2496, 4226, 7153, 12110, 20500, 34706, 58754, 99469, 168396, 285091, 482651, 817121, 1383372, 2342034, 3965038, 6712778, 11364682, 19240337, 32573779, 55147244, 93364021, 158064880, 267603180
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^8+x^7+x^6+x^5+2*x^4-x^3-1)/(x^7+x^5-x^4+x^3-2*x+1). - R. J. Mathar, Jan 19 2011
MATHEMATICA
LinearRecurrence[{2, 0, -1, 1, -1, 0, -1}, {1, 2, 4, 8, 13, 22, 37, 63, 106}, 40] (* Harvey P. Dale, Apr 03 2022 *)
CROSSREFS
Sequence in context: A023600 A164437 A164428 * A164414 A164411 A164443
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
Edited by Alois P. Heinz, Feb 14 2018
STATUS
approved