OFFSET
1,2
COMMENTS
(2n)!! is the product of first n even numbers, (2n-1)!! is the product of first n odd numbers.
MATHEMATICA
Table[Mod[(2n)!!, (2n-1)!!], {n, 20}] (* Harvey P. Dale, Sep 23 2020 *)
PROG
(Python)
o=e=1
for n in range(1, 99, 2):
o*=n
e*=n+1
print(str(e%o), end=', ')
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Nov 27 2013
STATUS
approved