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A020973
Expansion of 1/((1-7*x)*(1-10*x)*(1-11*x)).
1
1, 28, 527, 8330, 119361, 1607088, 20736787, 259516390, 3174562421, 38159361548, 452427201447, 5305418786850, 61660643651881, 711374339146408, 8156868543440507, 93047809667655710, 1056781696172883741
OFFSET
0,2
FORMULA
a(n) = 28*a(n-1) - 257*a(n-2) + 770*a(n-3) for n>=3. - Vincenzo Librandi, Mar 15 2011
a(n) = 21*a(n-1) - 110*a(n-2) + 7^n for n>1, a(0)=1, a(1)=28. - Vincenzo Librandi, Mar 15 2011
a(n) = (3*11^(n+2) - 4*10^(n+2) + 7^(n+2))/12. - Yahia Kahloune, Jun 30 2013
MATHEMATICA
CoefficientList[Series[1/((1-7x)(1-10x)(1-11x)), {x, 0, 50}], x] (* G. C. Greubel, May 31 2018 *)
PROG
(PARI) x='x+O('x^30); Vec(1/((1-7*x)*(1-10*x)*(1-11*x))) \\ G. C. Greubel, May 31 2018
(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-7*x)*(1-10*x)*(1-11*x)))); // G. C. Greubel, May 31 2018
CROSSREFS
Sequence in context: A024347 A025984 A020977 * A023947 A020972 A025957
KEYWORD
nonn,easy
STATUS
approved