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A164405 Number of binary strings of length n with no substrings equal to 0010 or 1100 1
14, 24, 41, 70, 120, 207, 358, 620, 1074, 1860, 3220, 5573, 9644, 16688, 28877, 49970, 86472, 149640, 258954, 448124, 775485, 1341986, 2322320, 4018795, 6954558, 12034920, 20826530, 36040488, 62368376, 107929017, 186772104, 323210752 (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 (2,0,-1,0,0,1).

FORMULA

G.f.: x^4*(14-4*x-7*x^2+2*x^3+4*x^4+8*x^5)/(1-2*x+x^3-x^6). - R. J. Mathar, Nov 30 2011

MAPLE

f:= gfun:-rectoproc({a(n) = 2*a(n-1)-a(n-3)+a(n-6), seq(a(i)=[14, 24, 41, 70, 120, 207][i-3], i=4..9)}, a(n), remember):

map(f, [$4..35]); # Robert Israel, Sep 19 2017

MATHEMATICA

LinearRecurrence[{2, 0, -1, 0, 0, 1}, {14, 24, 41, 70, 120, 207}, 50] (* G. C. Greubel, Sep 19 2017 *)

PROG

(PARI) x='x+O('x^50); Vec(x^4*(14-4*x-7*x^2+2*x^3+4*x^4+8*x^5 )/(1-2*x+ x^3 -x^6)) \\ G. C. Greubel, Sep 19 2017

CROSSREFS

Sequence in context: A164399 A164396 A164404 * A164395 A164394 A211323

Adjacent sequences:  A164402 A164403 A164404 * A164406 A164407 A164408

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 14 2009

STATUS

approved

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Last modified November 19 00:50 EST 2017. Contains 294912 sequences.