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A018070
Expansion of 1/((1-3x)(1-8x)(1-11x)).
1
1, 22, 339, 4532, 56357, 672210, 7813303, 89300464, 1009144713, 11315328398, 126186563867, 1401795991596, 15529706751469, 171706382611786, 1895807080277631, 20910172869786728, 230462261504563025
OFFSET
0,2
FORMULA
a(n) = 22*a(n-1) - 145*a(n-2) + 264*a(n-3) for n>2; a(0)=1, a(1)=22, a(2)=339. - Vincenzo Librandi, Jul 02 2013
a(n) = 19*a(n-1) - 88*a(n-2) + 3^n. - Vincenzo Librandi, Jul 02 2013
a(n) = (5*11^(n+2) - 8^(n+3) + 3^(n+3))/120. - Yahia Kahloune, Jul 06 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - 3 x) (1 - 8 x) (1 - 11 x)), {x, 0, 30}], x] (* Vincenzo Librandi, Jul 02 2013 *)
LinearRecurrence[{22, -145, 264}, {1, 22, 339}, 30] (* Harvey P. Dale, Jan 22 2014 *)
PROG
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-3*x)*(1-8*x)*(1-11*x)))); /* or */ I:=[1, 22, 339]; [n le 3 select I[n] else 22*Self(n-1)-145*Self(n-2)+264*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 02 2013
CROSSREFS
Sequence in context: A018090 A021274 A021534 * A332873 A019490 A021254
KEYWORD
nonn,easy
STATUS
approved