OFFSET
0,2
FORMULA
From Amiram Eldar, Nov 16 2020: (Start)
Sum_{n>=0} 1/a(n) = A334379.
Sum_{n>=0} (-1)^n/a(n) = A334632. (End)
MATHEMATICA
Table[((2n)!)^(2), {n, 0, 10}]
((2*Range[0, 20])!)^2 (* Harvey P. Dale, Jul 14 2011 *)
PROG
(PARI) a(n) = ((2*n)!)^2; \\ Michel Marcus, Nov 16 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Oct 22 2007
STATUS
approved