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A249996 Expansion of 1/((1+2*x)*(1+3*x)*(1-4*x)). 3
1, -1, 15, -5, 191, 99, 2455, 3515, 33231, 74899, 474695, 1371435, 7071871, 23520899, 108399735, 390617755, 1691480111, 6378762099, 26676785575, 103221406475, 423343881951, 1661998662499, 6742129440215, 26686105001595, 107591675061391, 427824901526099, 1718925069371655 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Colin Barker, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (-1,14,24).

FORMULA

G.f.: 1 / ((1+2*x)*(1+3*x)*(1-4*x)).

a(n) = ( 2^(3+2*n) + (3^(3+n)-7*2^(1+n))*(-1)^n )/21. - Colin Barker, Dec 29 2014

a(n) = -a(n-1) + 14*a(n-2) + 24*a(n-3). - Colin Barker, Dec 29 2014

PROG

(PARI) Vec(1/((1+2*x)*(1+3*x)*(1-4*x)) + O(x^50)) \\ Michel Marcus, Dec 29 2014

CROSSREFS

Cf. A016269: expansion of 1/((1-2*x)*(1-3*x)*(1-4*x)).

Cf. A249992, A249993, A249994, A249995.

Sequence in context: A147060 A110791 A241361 * A128251 A292307 A064107

Adjacent sequences:  A249993 A249994 A249995 * A249997 A249998 A249999

KEYWORD

sign,easy

AUTHOR

Alex Ratushnyak, Dec 28 2014

STATUS

approved

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Last modified July 15 22:48 EDT 2019. Contains 325061 sequences. (Running on oeis4.)