OFFSET
1,1
COMMENTS
EXAMPLE
45181 = |0!! - 3!! + 6!! - 9!! + 12!!| is prime.
MATHEMATICA
Select[#, PrimeQ] &@ Table[Abs@ Sum[(-1)^k*(3 k)!!, {k, 0, n}], {n, 0, 30}] (* Michael De Vlieger, Jul 19 2017 *)
CROSSREFS
KEYWORD
easy,nonn,fini,full
AUTHOR
XU Pingya, Jul 19 2017
STATUS
approved