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A025440
Expansion of 1/((1-2x)(1-3x)(1-4x)(1-6x)).
0
1, 15, 145, 1155, 8281, 55755, 360865, 2276835, 14126761, 86681595, 527948785, 3199656915, 19327384441, 116486845035, 701025539905, 4214614099395, 25321657045321, 152066219226075, 912943584910225, 5479850073412275, 32887865154533401, 197362281160304715
OFFSET
0,2
FORMULA
a(n) = -2^n +9*3^n -16*4^n +9*6^n. - R. J. Mathar, Jun 30 2013
a(n) = 15*a(n-1)-80*a(n-2)+180*a(n-3)-144*a(n-4). - Vincenzo Librandi, Jul 03 2015
a(n) = 3^n - 2^n + 10*a(n-1)-24*a(n-2). - Vincenzo Librandi, Jul 03 2015
MATHEMATICA
LinearRecurrence[{15, -80, 180, -144}, {1, 15, 145, 1155}, 50] (* Vincenzo Librandi, Jul 03 2015 *)
CoefficientList[Series[1/((1-2x)(1-3x)(1-4x)(1-6x)), {x, 0, 30}], x] (* Harvey P. Dale, Aug 21 2021 *)
PROG
(PARI) Vec(1/((1-2*x)*(1-3*x)*(1-4*x)*(1-6*x)) + O(x^30)) \\ Michel Marcus, Jul 03 2015
CROSSREFS
Sequence in context: A368075 A163799 A206810 * A155638 A252982 A245755
KEYWORD
nonn
AUTHOR
STATUS
approved