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A018208 Expansion of 1/((1-3x)(1-11x)(1-12x)). 1
1, 26, 475, 7520, 110341, 1545446, 20980975, 278565740, 3637529881, 46892529266, 598374287875, 7572794935160, 95188878040621, 1189735265087486, 14798979200433175, 183331466632763780 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

Index to sequences with linear recurrences with constant coefficients, signature (26,-201,396).

FORMULA

a(0)=1, a(1)=26, a(2)=475; for n>2, a(n) = 26*a(n-1) -201*a(n-2)+396*a(n-3). - Vincenzo Librandi, Jul 02 2013

a(n) = 23*a(n-1) -132*a(n-2) +3^n. - Vincenzo Librandi, Jul 02 2013

a(n) = (8*12^(n+2) - 9*11^(n+2) + 3^(n+2))/72. [Yahia Kahloune, Jul 07 2013]

MATHEMATICA

CoefficientList[Series[1 / ((1 - 3 x) (1 - 11 x) (1 - 12 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)*(1-11*x)*(1-12*x)))); /* or */ I:=[1, 26, 475]; [n le 3 select I[n] else 26*Self(n-1)-201*Self(n-2)+396*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 02 2013

CROSSREFS

Sequence in context: A019747 A163740 A021334 * A240190 A001723 A163201

Adjacent sequences:  A018205 A018206 A018207 * A018209 A018210 A018211

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified September 2 19:51 EDT 2014. Contains 246367 sequences.