OFFSET
0,2
COMMENTS
a(26) = 2 * 41 * 121157 * 160215276888781 * 1706504288791033 * 4123576055576581869533. Thus a(n) are multiples of 41 for n >= 26.
MATHEMATICA
Table[Abs@ Sum[(-1)^k*(3 k)!!, {k, 0, n}], {n, 0, 15}] (* Michael De Vlieger, Jul 19 2017 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
XU Pingya, Jul 19 2017
STATUS
approved