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A028055
Expansion of 1/((1-3x)(1-5x)(1-6x)(1-9x)).
0
1, 23, 340, 4130, 45031, 459893, 4504690, 42928160, 401635861, 3711270563, 34005047440, 309788905790, 2811170579491, 25442007146033, 229842147512590, 2073840099225020, 18696506927851921, 168462145714550303
OFFSET
0,2
FORMULA
a(n)=(9^(n+3)-8*6^(n+3)+9*5^(n+3)-2*3^(n+3))/72. [Yahia Kahloune, Jun 07 2013]
a(0)=1, a(1)=23, a(2)=340, a(3)=4130, a(n)=23*a(n-1)-189*a(n-2)+ 657*a(n-3)- 810*a(n-4). - Harvey P. Dale, Jul 01 2015
MATHEMATICA
CoefficientList[Series[1/((1-3x)(1-5x)(1-6x)(1-9x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{23, -189, 657, -810}, {1, 23, 340, 4130}, 30] (* Harvey P. Dale, Jul 01 2015 *)
PROG
(PARI) a(n)=(9^(n+3)-8*6^(n+3)+9*5^(n+3)-2*3^(n+3))/72 \\ Charles R Greathouse IV, Jun 07 2013
CROSSREFS
Sequence in context: A163512 A028059 A299710 * A026324 A028039 A002118
KEYWORD
nonn,easy
AUTHOR
STATUS
approved