OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (24,-216,864,-1296).
FORMULA
G.f.: 6*x*(1 + 24*x + 36*x^2)/(1 - 6*x)^4. - Vincenzo Librandi, Feb 08 2013
a(n) = 24*a(n-1) - 216*a(n-2) + 864*a(n-3) - 1296*a(n-4). - Vincenzo Librandi, Feb 09 2013
MATHEMATICA
CoefficientList[Series[6 x *(1+24 x + 36 x^2)/(1-6*x)^4, {x, 0, 30}], x] (* Vincenzo Librandi, Feb 08 2013 *)
LinearRecurrence[{24, -216, 864, -1296}, {0, 6, 288, 5832}, 20] (* Harvey P. Dale, Mar 12 2023 *)
PROG
(Magma) [n^3*6^n: n in [0..20]]; // Vincenzo Librandi, Feb 08 2013
(Magma) I:=[0, 6, 288, 5832]; [n le 4 select I[n] else 24*Self(n-1)-216*Self(n-2)+864*Self(n-3)-1296*Self(n-4): n in [1..30]]; // Vincenzo Librandi, Feb 09 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Apr 07 2007
STATUS
approved