|
|
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
|
|
|
FORMULA
|
G.f.: 1/((1-3*x)*(1-11*x)*(1-12*x)).
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) = (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 *)
LinearRecurrence[{26, -201, 396}, {1, 26, 475}, 20] (* Harvey P. Dale, Jul 04 2017 *)
|
|
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
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|