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A021854 Expansion of 1/((1-x)(1-4x)(1-7x)(1-8x)). 1
1, 20, 265, 2940, 29601, 280740, 2558905, 22683980, 197048401, 1685772660, 14253277545, 119401486620, 992861126401, 8206523123780, 67497981692185, 552905862106860, 4513706683463601, 36742894880462100 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

FORMULA

a(n) = (9*8^(n+3) - 14*7^(n+3) + 7*4^(n+3) - 2)/252. [Yahia Kahloune, Jul 05 2013]

MATHEMATICA

CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 7 x)  (1 - 8 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)

CROSSREFS

Sequence in context: A208948 A278408 A229562 * A025939 A278773 A021824

Adjacent sequences:  A021851 A021852 A021853 * A021855 A021856 A021857

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified April 23 09:35 EDT 2019. Contains 322385 sequences. (Running on oeis4.)