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A019958
Expansion of 1/((1-5*x)*(1-7*x)*(1-10*x)).
1
1, 22, 329, 4178, 48621, 537222, 5744929, 60136378, 620564021, 6341995022, 64384199529, 650640568578, 6554239839421, 65878458172822, 661143103694129, 6627971208280778, 66395645870074821, 664768758151070622
OFFSET
0,2
FORMULA
a(n) = 5*5^n/2 - 49*7^n/6 + 20*10^n/3. - R. J. Mathar, Jun 29 2013
From Vincenzo Librandi, Jul 03 2013: (Start)
a(n) = 22*a(n-1) - 155*a(n-2) + 350*a(n-3); a(0)=1, a(1)=22, a(2)=329.
a(n) = 17*a(n-1) - 70*a(n-2) + 5^n. (End)
MATHEMATICA
CoefficientList[Series[1/((1-5x)(1-7x)(1-10x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 03 2013 *)
LinearRecurrence[{22, -155, 350}, {1, 22, 329}, 20] (* G. C. Greubel, Nov 22 2018 *)
PROG
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-5*x)*(1-7*x)*(1-10*x)))); /* or */ I:=[1, 22, 329]; [n le 3 select I[n] else 22*Self(n-1)-155*Self(n-2)+350*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 03 2013
(PARI) x='x+O('x^20); Vec(1/((1-5*x)*(1-7*x)*(1-10*x))) \\ G. C. Greubel, Nov 22 2018
(Sage) s=(1/((1-5*x)*(1-7*x)*(1-10*x))).series(x, 20); s.coefficients(x, sparse=False) # G. C. Greubel, Nov 22 2018
CROSSREFS
Sequence in context: A047868 A002539 A230965 * A021644 A021834 A019671
KEYWORD
nonn,easy
STATUS
approved