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A028150
Expansion of 1/((1-4x)(1-7x)(1-9x)(1-11x)).
0
1, 31, 614, 9926, 142995, 1915077, 24414088, 300588892, 3608146949, 42498447563, 493420114122, 5665664143698, 64496965543063, 729264545514289, 8201673484111916, 91847355888191144, 1025058980614782537
OFFSET
0,2
FORMULA
a(n) = (15*11^(n+3)-42*9^(n+3)+5*7^(n+4)-2*4^(n+4))/840. [Yahia Kahloune, May 29 2013]
MATHEMATICA
CoefficientList[Series[1/((1 - 4 x) (1 - 7 x) (1 - 9 x) (1 - 11 x)), {x, 0, 20}], x] (* Wesley Ivan Hurt, Apr 25 2017 *)
CROSSREFS
Sequence in context: A028182 A028155 A028175 * A028173 A301769 A028142
KEYWORD
nonn
STATUS
approved