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A017917
Expansion of 1/((1-3x)(1-5x)(1-11x)).
1
1, 19, 258, 3110, 35651, 399609, 4433668, 48962380, 539552901, 5939935199, 65363612678, 719121544050, 7910946538951, 87023461294789, 957273325857288, 10530082856852120, 115831292830529801, 1274146128290750379
OFFSET
0,2
FORMULA
a(0)=1, a(1)=19, a(2)=258; for n>2, a(n) = 19*a(n-1) -103*a(n-2) +165*a(n-3). - Vincenzo Librandi, Jul 01 2013
a(n) = 16*a(n-1) -55*a(n-2) +3^n. - Vincenzo Librandi, Jul 01 2013
a(n) = (11^(n+2) - 4*5^(n+2) + 3^(n+3))/48. [Yahia Kahloune, Jul 06 2013]
MATHEMATICA
CoefficientList[Series[1 / ((1 - 3 x) (1 - 5 x) (1 - 11 x)), {x, 0, 30}], x] (* Vincenzo Librandi, Jul 01 2013 *)
PROG
(Magma) I:=[1, 19, 258]; [n le 3 select I[n] else 19*Self(n-1)-103*Self(n-2)+165*Self(n-3): n in [1..20]]; /* or */ m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-3*x)*(1-5*x)*(1-11*x)))); // Vincenzo Librandi, Jul 01 2013
CROSSREFS
Sequence in context: A255722 A016313 A335515 * A016308 A014923 A081036
KEYWORD
nonn,easy
AUTHOR
STATUS
approved