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A168057 Expansion of (1+8x^2+8x^3)/((1-2x)^2*(1+2x+4x^2)). 3
1, 2, 12, 40, 80, 224, 576, 1152, 2816, 6656, 13312, 30720, 69632, 139264, 311296, 688128, 1376256, 3014656, 6553600, 13107200, 28311552, 60817408, 121634816, 260046848, 553648128, 1107296256, 2348810240, 4966055936, 9932111872 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Hankel transform of A168058 is (-1)^n*a(n).

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (2,0,8,-16).

FORMULA

a(n) = 2^n*A168056(n).

MATHEMATICA

CoefficientList[Series[(1+8x^2+8x^3)/((1-2x)^2(1+2x+4x^2)), {x, 0, 50}], x] (* Harvey P. Dale, Mar 24 2011 *)

LinearRecurrence[{2, 0, 8, -16}, {1, 2, 12, 40}, 50] (* G. C. Greubel, Jul 08 2016 *)

CROSSREFS

Sequence in context: A190022 A086602 A019006 * A290131 A008911 A005719

Adjacent sequences:  A168054 A168055 A168056 * A168058 A168059 A168060

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Nov 17 2009

STATUS

approved

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Last modified February 21 06:40 EST 2019. Contains 320371 sequences. (Running on oeis4.)