Hi all,
The answer I know is 312 x 311 x 310 x 309 x 308 = 2,862,766,146,240 = 2.86277E+12. The arguments are 312 and 5.
Using the notation myfunction(x,y) the result is (x)*(x-1)*(x-2)*(x-3)*(x-4)*..etc...*(x-(y+1))
Another example, myfunction(17,10) = 70572902400...