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A028184
Expansion of 1/((1-5x)(1-7x)(1-9x)(1-10x)).
1
1, 31, 608, 9650, 135471, 1756461, 21553078, 254114080, 2907590741, 32510311691, 356977004748, 3863433611310, 41325142341211, 437804739243721, 4601385756887618, 48040443020269340, 498759633052498881, 5153605455623560551, 53035826592972273688
OFFSET
0,2
FORMULA
a(n)=(8*10^(n+3)-15*9^(n+3)+10*7^(n+3)-3*5^(n+3))/120. [Yahia Kahloune, Jun 04 2013]
MATHEMATICA
CoefficientList[Series[1/((1-5x)(1-7x)(1-9x)(1-10x)), {x, 0, 20}], x] (* or *) LinearRecurrence[{31, -353, 1745, -3150}, {1, 31, 608, 9650}, 20] (* Harvey P. Dale, Apr 01 2018 *)
PROG
(Magma) I:=[1, 31, 608, 9650]; [n le 4 select I[n] else 31*Self(n-1)-353*Self(n-2)+1745*Self(n-3)-3150*Self(n-4): n in [1..25]]; // Vincenzo Librandi, Apr 02 2018
CROSSREFS
Sequence in context: A360761 A005462 A028201 * A215794 A028182 A028155
KEYWORD
nonn
AUTHOR
STATUS
approved