OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (25,-186,360).
FORMULA
a(0)=1, a(1)=25, a(2)=439; for n>2. a(n) = 25*a(n-1) -186*a(n-2) +360*a(n-3). - Vincenzo Librandi, Jul 02 2013
a(n) = 22*a(n-1) -120*a(n-2) +3^n. - Vincenzo Librandi, Jul 02 2013
a(n) = (7*12^(n+2) - 9*10^(n+2) + 2*3^(n+2))/126. [Yahia Kahloune, Jul 06 2013]
MATHEMATICA
CoefficientList[Series[1 / ((1 - 3 x) (1 - 10 x) (1 - 12 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 02 2013 *)
LinearRecurrence[{25, -186, 360}, {1, 25, 439}, 20] (* Harvey P. Dale, Jul 20 2022 *)
PROG
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-3*x)*(1-10*x)*(1-12*x)))); // Vincenzo Librandi, Jul 02 2013
(Magma) I:=[1, 25, 439]; [n le 3 select I[n] else 25*Self(n-1)-186*Self(n-2)+360*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 02 2013
CROSSREFS
KEYWORD
nonn,easy,changed
AUTHOR
STATUS
approved