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A016313
Expansion of 1/((1-2*x)*(1-7*x)*(1-10*x)).
2
1, 19, 257, 3047, 33825, 361767, 3782353, 38976439, 397835009, 4034844935, 40743914289, 410207399511, 4121451795553, 41350162566823, 414451137963665, 4151157965737463, 41558105760145857, 415906740320988231
OFFSET
0,2
FORMULA
a(0)=1, a(1)=19, a(2)=257, a(n)=19*a(n-1)-104*a(n-2)+140*a(n-3). - Harvey P. Dale, May 02 2012
a(n) = 2^n/10 - 49*7^n/15 + 25*10^n/6. - R. J. Mathar, Jun 23 2013
a(n) = 17*a(n-1) - 70*a(n-2) + 2^n. - Vincenzo Librandi, Jun 26 2013
MATHEMATICA
CoefficientList[Series[1/((1-2x)(1-7x)(1-10x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{19, -104, 140}, {1, 19, 257}, 30] (* Harvey P. Dale, May 02 2012 *)
PROG
(PARI) Vec(1/((1-2*x)*(1-7*x)*(1-10*x))+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012
(Magma) I:=[1, 19, 257]; [n le 3 select I[n] else 19*Self(n-1)-104*Self(n-2) +140*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jun 26 2013
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-2*x)*(1-7*x)*(1-10*x)))); // Vincenzo Librandi, Jun 26 2013
CROSSREFS
Sequence in context: A016316 A021154 A255722 * A335515 A017917 A016308
KEYWORD
nonn,easy
STATUS
approved