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A021049
Expansion of 1/((1-x)(1-2x)(1-3x)(1-10x)).
1
1, 16, 185, 1940, 19701, 197976, 1982785, 19837180, 198400301, 1984089536, 19841156985, 198412358820, 1984125963301, 19841266774696, 198412689204785, 1984126956486860, 19841269758316701, 198412698163773456
OFFSET
0,2
FORMULA
a(n) = -(1/18)+2^n-(27/14)*3^n+(125/63)*10^n. [Antonio Alberto Olivares, May 22 2012]
a(0)=1, a(1)=16; for n>1, a(n) = 13*a(n-1) -30*a(n-2) +2^n - 1. - Vincenzo Librandi, Jul 05 2013
a(0)=1, a(1)=16, a(2)=185, a(3)=1940; for n>3, a(n) = 16*a(n-1) -71*a(n-2) +116*a(n-3) -60*a(n-4). - Vincenzo Librandi, Jul 05 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 2 x) (1 - 3 x) (1 - 10 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 05 2013 *)
PROG
(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-2*x)*(1-3*x)*(1-10*x)))); /* or */ I:=[1, 16, 185, 1940]; [n le 4 select I[n] else 16*Self(n-1)-71*Self(n-2)+116*Self(n-3)-60*Self(n-4): n in [1..25]]; // Vincenzo Librandi, Jul 05 2013
CROSSREFS
Sequence in context: A125428 A203391 A016249 * A067308 A016244 A240361
KEYWORD
nonn,easy
AUTHOR
STATUS
approved