F =
((1. - Subscript[p, 4])^(-Subscript[p, 3]) - (1. - Subscript[p, 4]*
Exp[-Subscript[p, 1]*Subscript[x, i]^Subscript[p,2]])^(-Subscript[p,3]))/
((1. - Subscript[p, 4])^(-Subscript[p, 3]) - 1.)
f = FullSimplify[D[F, Subscript[x, i]]]
L := Product[f, {i, 1, n}] // AbsoluteTiming
In Mathematica 7.0, how can I get the Product
expression shown above to evaluate in a reasonable time without specifying n
?.