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A080921 a(n) = 2*a(n-1) + 48*a(n-2), a(0)=0, a(1)=1. 2
0, 1, 2, 52, 200, 2896, 15392, 169792, 1078400, 10306816, 72376832, 639480832, 4753049600, 40201179136, 308548739072, 2546754076672, 19903847628800, 162051890937856, 1279488468058112, 10337467701133312, 82090381869056000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Essentially the same as A053455: a(n) = A053455(n-1), n>=1.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (2,48).

FORMULA

a(n) = (8^n - (-6)^n)/14.

a(n) = Sum{k=1..n, binomial(n, 2k-1) * 7^(2(k-1)) }

G.f.: x/((1+6*x)*(1-8*x)).

a(n) = A053455(n-1), n>=1. [R. J. Mathar, Sep 18 2008]

MATHEMATICA

CoefficientList[Series[x / ((1 + 6 x) (1 - 8 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Aug 05 2013 *)

LinearRecurrence[{2, 48}, {0, 1}, 30] (* Harvey P. Dale, Jan 20 2016 *)

CROSSREFS

Cf. A079773, A051958, A015441, A080920.

Sequence in context: A030264 A129742 A105647 * A053455 A297947 A298556

Adjacent sequences:  A080918 A080919 A080920 * A080922 A080923 A080924

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Feb 24 2003

STATUS

approved

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Last modified June 4 11:32 EDT 2020. Contains 334825 sequences. (Running on oeis4.)