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A164408 Number of binary strings of length n with no substrings equal to 0000 0001 or 0011. 1
13, 23, 40, 68, 118, 203, 349, 602, 1036, 1784, 3073, 5291, 9112, 15692, 27022, 46535, 80137, 138002, 237652, 409256, 704773, 1213679, 2090056, 3599252, 6198214, 10673843, 18381253, 31654058, 54510940, 93872408, 161656153, 278385443 (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 (1, 1, 1, -1).

FORMULA

G.f.: x^4*(13+10*x+4*x^2-8*x^3) / ( 1-x-x^2-x^3+x^4 ). - R. J. Mathar, Nov 28 2011

MATHEMATICA

CoefficientList[Series[(13 + 10*x + 4*x^2 - 8*x^3)/(1 - x - x^2 - x^3 + x^4), {x, 0, 50}], x] (* Wesley Ivan Hurt, Jan 10 2017 *)

LinearRecurrence[{1, 1, 1, -1}, {13, 23, 40, 68}, 50] (* G. C. Greubel, Sep 19 2017 *)

PROG

(PARI) x='x+O('x^50); Vec(x^4*(13+10*x+4*x^2-8*x^3)/(1-x-x^2-x^3+x^4)) \\ G. C. Greubel, Sep 19 2017

CROSSREFS

Sequence in context: A089714 A070219 A046119 * A164416 A164491 A164434

Adjacent sequences:  A164405 A164406 A164407 * A164409 A164410 A164411

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 14 2009

STATUS

approved

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Last modified December 6 04:20 EST 2021. Contains 349562 sequences. (Running on oeis4.)