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A018090 Expansion of 1/((1-3x)(1-9x)(1-10x)). 1
1, 22, 337, 4450, 54301, 631462, 7111417, 78287530, 847442101, 9055541902, 95785566097, 1004927161810, 10472915657101, 108541954516342, 1119734731454377, 11506184005511290, 117841370316867301 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (22,-147,270).

FORMULA

a(0)=1, a(1)=22, a(2)=337; for n>2 a(n) = 22*a(n-1) -147*a(n-2) +270*a(n-3). - Vincenzo Librandi, Jul 02 2013

a(n) = 19*a(n-1) -90*a(n-2) +3^n. - Vincenzo Librandi, Jul 02 2013

a(n) = (6*10^(n+2) - 7*9^(n+2) + 3^(n+2))/42. [Yahia Kahloune, Jul 06 2013]

MATHEMATICA

CoefficientList[Series[1 / ((1 - 3 x) (1 - 9 x) (1 - 10 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 02 2013 *)

PROG

(MAGMA) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-3*x)*(1-9*x)*(1-10*x)))); /* or */ I:=[1, 22, 337]; [n le 3 select I[n] else 22*Self(n-1)-147*Self(n-2)+270*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 02 2013

CROSSREFS

Sequence in context: A021794 A348134 A223812 * A021274 A021534 A018070

Adjacent sequences:  A018087 A018088 A018089 * A018091 A018092 A018093

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified October 26 00:52 EDT 2021. Contains 348256 sequences. (Running on oeis4.)