Given the definition

"n!!...!=n(n-k)(n-2k)...(n mod k), if k doesn’t divide n,
n!!...!=n(n-k)(n-2k)...k, if k divides n (There are k marks ! in the
both cases)."

when n = k what should be the answer?
Should it be
   = n * k (cos k divides n)
or just
   = n

when k > n what should be the answer?
Should it be
   = n * (n mod k)
   = n * n

or just
   = n

Anyone got any idea?