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A020970
Expansion of 1/((1-7*x)*(1-9*x)*(1-10*x)).
0
1, 26, 453, 6610, 87221, 1079106, 12770773, 146348690, 1637020341, 17972357986, 194425446293, 2078548587570, 22007974284661, 231179027537666, 2412362060669013, 25033514235831250, 258557417951152181
OFFSET
0,2
FORMULA
G.f.: 1/((1-7*x)*(1-9*x)*(1-10*x)).
a(n) = 26*a(n-1) - 223*a(n-2) + 630*a(n-3), n>=3. - Vincenzo Librandi, Mar 15 2011
a(n) = 19*a(n-1) - 90*a(n-2) + 7^n, a(0)=1, a(1)=26. - Vincenzo Librandi, Mar 15 2011
a(n) = (7^(n+2)-3*9^(n+2)+2*10^(n+2))/6. - Bruno Berselli, Mar 15 2011
MATHEMATICA
CoefficientList[Series[1/((1-7x)(1-9x)(1-10x)), {x, 0, 50}], x] (* G. C. Greubel, May 31 2018 *)
PROG
(PARI) x='x+O('x^30); Vec(1/((1-7*x)*(1-9*x)*(1-10*x))) \\ G. C. Greubel, May 31 2018
(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-7*x)*(1-9*x)*(1-10*x)))); // G. C. Greubel, May 31 2018
CROSSREFS
Sequence in context: A025996 A023540 A025979 * A023953 A020968 A025955
KEYWORD
nonn
STATUS
approved