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A249997 Expansion of 1/((1-x)*(1+3*x)*(1-4*x)). 2
1, 2, 15, 40, 221, 702, 3355, 11780, 52041, 193402, 817895, 3138720, 12953461, 50618102, 206059635, 813476860, 3286192481, 13047914802, 52482224575, 209057202200, 838843897101, 3347530323502, 13413657088715, 53584020970740, 214547906035321, 857556157684202 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..25.

Index entries for linear recurrences with constant coefficients, signature (2,11,-12).

FORMULA

a(n) = (-1)^n*3^(n+2)/28 + 4^(n+2)/21 -1/12. - R. J. Mathar, Jan 09 2015

CROSSREFS

Cf. A016208, A099621, A249998.

Sequence in context: A070170 A033568 A200156 * A032016 A254856 A001007

Adjacent sequences:  A249994 A249995 A249996 * A249998 A249999 A250000

KEYWORD

nonn,easy

AUTHOR

Alex Ratushnyak, Dec 28 2014

STATUS

approved

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Last modified February 18 05:48 EST 2018. Contains 299298 sequences. (Running on oeis4.)