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 A164431 Number of binary strings of length n with no substrings equal to 0000 0011 or 1101 1
 13, 21, 34, 54, 86, 139, 225, 364, 590, 956, 1547, 2503, 4050, 6552, 10600, 17151, 27751, 44902, 72654, 117558, 190213, 307771, 497984, 805754, 1303736, 2109489, 3413225, 5522714, 8935940, 14458656, 23394597, 37853253, 61247850, 99101102 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,1 LINKS R. H. Hardin, Table of n, a(n) for n=4..500 Index entries for linear recurrences with constant coefficients, signature (2,-1,1,-1,0,1). FORMULA G.f. -x^4*(13-5*x+5*x^2-6*x^3+4*x^4+8*x^5) / ( (x^2+x-1)*(x^4-x^3+x^2-x+1) ). - R. J. Mathar, Jan 19 2011 MATHEMATICA LinearRecurrence[{2, -1, 1, -1, 0, 1}, {13, 21, 34, 54, 86, 139}, 40] (* Harvey P. Dale, May 19 2016 *) CROSSREFS Sequence in context: A164481 A164433 A164479 * A164497 A164503 A067516 Adjacent sequences: A164428 A164429 A164430 * A164432 A164433 A164434 KEYWORD nonn AUTHOR R. H. Hardin Aug 14 2009 STATUS approved

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Last modified March 29 17:51 EDT 2023. Contains 361599 sequences. (Running on oeis4.)