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A250101
Expansion of (18*x+86*x^2)/(1-11*x^2-150*x^3).
1
0, 18, 86, 198, 3646, 15078, 69806, 712758, 3029566, 18311238, 140238926, 655858518, 4289313886, 28250282598, 145561230446, 954150191478, 5838715924606, 32329836673158, 207348403892366, 1231435592095638, 7130307943789726, 44648052096906918, 263148726196032686
OFFSET
0,2
LINKS
Ira M. Gessel, Rational Functions With Nonnegative Integer Coefficients, slides, 50th Séminaire Lotharingien de Combinatoire, 2003.
FORMULA
From Colin Barker, Apr 14 2016: (Start)
a(n) = 2^(1+n)*3^n - (-3-4*i)^n - (-3+4*i)^n where i is the imaginary unit.
a(n) = 11*a(n-2) + 150*a(n-3) for n>2.
(End)
PROG
(PARI) concat(0, Vec((18*x+86*x^2)/(1-11*x^2-150*x^3) + O(x^30))) \\ Michel Marcus, Aug 28 2015
(PARI) a(n) = 2^(1+n)*3^n - (-3-4*I)^n - (-3+4*I)^n \\ Colin Barker, Apr 14 2016
CROSSREFS
Sequence in context: A281372 A124935 A126405 * A141842 A215191 A063788
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Nov 15 2014
STATUS
approved