A016301 Expansion of 1/((1-2*x)*(1-5*x)*(1-11*x)).

1, 18, 237, 2810, 31941, 356538, 3947917, 43557210, 479780181, 5280836858, 58105480797, 639241667610, 7032065242021, 77354752161978, 850912446296877, 9360087771874010, 102961219803721461, 1132574689406603898

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..100

Index entries for linear recurrences with constant coefficients, signature (18,-87,110).

Formula

From Vincenzo Librandi, Aug 25 2011: (Start)

a(n) = 18*a(n-1) - 87*a(n-2) + 110*a(n-3); a(1)=1, a(2)=18, a(3)=237.

a(n) = 16*a(n-1) - 55*a(n-2) + 2^n; a(1)=1, a(2)=18. (End)

a(n) = (1/54)*(2*2^(2+n) - 3*5^(2+n) + 11^(2+n)). - Bruno Berselli, Aug 25 2011

Mathematica

CoefficientList[Series[1/((1-2x)(1-5x)(1-11x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{18, -87, 110}, {1, 18, 237}, 30] (* Vincenzo Librandi, Aug 25 2011 *)

Prog

(Magma) [ n eq 1 select 1 else n eq 2 select 18 else n eq 3 select 237 else 18*Self(n-1)-87*Self(n-2) +110*Self(n-3): n in [1..20] ]; // Vincenzo Librandi, Aug 25 2011
(PARI) Vec(1/((1-2*x)*(1-5*x)*(1-11*x))+O(x^18)) \\ Bruno Berselli, Aug 25 2011

Crossrefs

Sequence in context: A016256 A017065 A016252 * A058126 A016247 A021064

Adjacent sequences: A016298 A016299 A016300 * A016302 A016303 A016304

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved