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A121204 -2n+7^n-5^n. 1
0, 0, 20, 212, 1768, 13672, 102012, 745404, 5374160, 38400464, 272709604, 1928498596, 13597146552, 95668307256, 672119557196, 4717043931788, 33080342678944, 231867574534048, 1624598900644788, 11379821699044980 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (14,-60,82,-35).

FORMULA

G.f.: 4*x^2*(5-17*x)/((1-x)^2 (1-5*x)(1-7*x)). - Vincenzo Librandi. Feb 26 2013

a(n) = 14*a(n-1)-60*a(n-2)+82*a(n-3)-35*a(n-4). - Vincenzo Librandi, Feb 26 2013

MATHEMATICA

CoefficientList[Series[4 x^2 (5 - 17 x)/((1 - x)^2 (1 - 5 x)(1 - 7 x)), {x, 0, 30}], x] (* Vincenzo Librandi, Feb 26 2013 *)

PROG

(MAGMA) I:=[0, 0, 20, 212]; [n le 4 select I[n] else 14*Self(n-1)-60*Self(n-2)+82*Self(n-3)-35*Self(n-4): n in [1..20]]; // Vincenzo Librandi, Feb 26 2013

CROSSREFS

Cf. A074616.

Sequence in context: A007744 A304023 A219467 * A128823 A141790 A229575

Adjacent sequences:  A121201 A121202 A121203 * A121205 A121206 A121207

KEYWORD

nonn,easy

AUTHOR

Mohammad K. Azarian, Aug 19 2006

EXTENSIONS

Edited by Ray Chandler, Sep 06 2006

STATUS

approved

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Last modified August 24 03:51 EDT 2019. Contains 326260 sequences. (Running on oeis4.)