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A164409 Number of binary strings of length n with no substrings equal to 0000 0001 or 0100 1
13, 22, 39, 69, 121, 212, 372, 653, 1146, 2011, 3529, 6193, 10868, 19072, 33469, 58734, 103071, 180877, 317417, 557028, 977516, 1715421, 3010354, 5282803, 9270673, 16268897, 28549924, 50101624, 87922221, 154292742, 270764887, 475159253 (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)

FORMULA

G.f.: x^4*(13-4*x+8*x^2)/(1-2*x+x^2-x^3). - R. J. Mathar, Nov 30 2011

MATHEMATICA

LinearRecurrence[{2, -1, 1}, {13, 22, 39}, 50] (* G. C. Greubel, Sep 19 2017 *)

PROG

(PARI) x='x+O('x^50); Vec(x^4*(13-4*x+8*x^2)/(1-2*x+x^2-x^3)) \\ G. C. Greubel, Sep 19 2017

CROSSREFS

Sequence in context: A164445 A164418 A301788 * A301962 A298235 A111676

Adjacent sequences:  A164406 A164407 A164408 * A164410 A164411 A164412

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 14 2009

STATUS

approved

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Last modified December 3 21:17 EST 2021. Contains 349468 sequences. (Running on oeis4.)