Hi A.H.,
the input you use is very difficult to understand. Are there parenthesis somewhere? So you mean:
(Sqrt[2]^(-4))^16/(Sqrt[Pi]^(-4))^2
or
(Sqrt[2^(-4)])^16/(Sqrt[Pi^(-4)])^2
or
Sqrt[2^(-4)^16]/(Sqrt[Pi^(-4)^2]
or something else? When you write sqrtpi is that supposed to be a square root of something or use a variable name?
Here are some versions that work: interpretation 1, interpretation 2, interpretation 3.
Cheers,
Marco