OFFSET
0,2
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
FORMULA
a(n) = 3^n * Sum_{k=0..n} binomial(2*k,k)^3 / 3^k.
Recurrence: n^3*a(n) = (67*n^3 - 96*n^2 + 48*n - 8)*a(n-1) - 24*(2*n-1)^3*a(n-2). - Vaclav Kotesovec, Aug 13 2013
a(n) ~ 2^(6*n+6)/(61*(Pi*n)^(3/2)). - Vaclav Kotesovec, Aug 13 2013
MATHEMATICA
Table[3^n Sum[Binomial[2k, k]^3/3^k, {k, 0, n}], {n, 0, 20}] (* Vincenzo Librandi, Mar 26 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Nov 14 2009
EXTENSIONS
More terms from Sean A. Irvine, Apr 27 2010
STATUS
approved