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A028206
Expansion of 1/((1-6x)(1-7x)(1-9x)(1-12x)).
0
1, 34, 733, 12826, 199213, 2869258, 39283021, 519148762, 6689833645, 84640449322, 1056561931789, 13058296545658, 160199367141997, 1954490541959626, 23747047106341837, 287633422522201114
OFFSET
0,2
FORMULA
a(n) = 21*a(n-1) - 108*a(n-2) + 7^(n+1) - 6^(n+1), n >= 2. - Vincenzo Librandi, Mar 13 2011
a(n) = 7^(n+3)/10 - 9^(n+2)/2 - 2*6^(n+1) + 8*12^(n+1)/5. - R. J. Mathar, Mar 18 2011
MATHEMATICA
CoefficientList[Series[1/((1-6x)(1-7x)(1-9x)(1-12x)), {x, 0, 20}], x] (* or *) LinearRecurrence[{34, -423, 2286, -4536}, {1, 34, 733, 12826}, 20] (* Harvey P. Dale, Dec 11 2017 *)
CROSSREFS
Sequence in context: A028211 A028207 A028193 * A028192 A028161 A028188
KEYWORD
nonn
STATUS
approved