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A078006 Expansion of (1-x)/(1-x-2*x^2-2*x^3). 1
1, 0, 2, 4, 8, 20, 44, 100, 228, 516, 1172, 2660, 6036, 13700, 31092, 70564, 160148, 363460, 824884, 1872100, 4248788, 9642756, 21884532, 49667620, 112722196, 255826500, 580606132, 1317703524, 2990568788, 6787188100, 15403732724, 34959246500, 79341088148, 180067046596 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..999

Index entries for linear recurrences with constant coefficients, signature (1, 2, 2).

FORMULA

a(0)=1, a(1)=0, a(2)=2, a(n)=a(n-1)+2*a(n-2)+2*a(n-3) [From Harvey P. Dale, Sep 25 2011]

MATHEMATICA

CoefficientList[Series[(1-x)/(1-x-2x^2-2x^3), {x, 0, 40}], x] (* or *) LinearRecurrence[{1, 2, 2}, {1, 0, 2}, 41] (* Harvey P. Dale, Sep 25 2011 *)

PROG

(PARI) Vec((1-x)/(1-x-2*x^2-2*x^3)+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012

CROSSREFS

Sequence in context: A272122 A105319 A051389 * A288476 A056952 A225585

Adjacent sequences:  A078003 A078004 A078005 * A078007 A078008 A078009

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 17 2002

STATUS

approved

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Last modified January 17 23:15 EST 2019. Contains 319251 sequences. (Running on oeis4.)