OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
FORMULA
G.f.: 1728*x*(1 + 4*x + x^2)/(1 - x)^4. - Vincenzo Librandi, Jul 05 2014
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>3. - Vincenzo Librandi, Jul 05 2014
MATHEMATICA
Table[1728 n^3, {n, 0, 40}] (* or *) CoefficientList[Series[1728 x (1 + 4 x + x^2)/(1 - x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Jul 05 2014 *)
PROG
(Maxima) makelist((12*n)^3, n, 0, 30); /* Martin Ettl, Oct 21 2012 */
(Magma) [1728*n^3: n in [0..40]] /* or */ I:=[0, 1728, 13824, 46656]; [n le 4 select I[n] else 4*Self(n-1)-6*Self(n-2)+4*Self(n-3)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Jul 05 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved