Suppose I want to sum a function, $f(\{m_a\})$, of several variables, $m_a$, $a=1,..,n$, which run over ranges, $1,...,k[[a]]$, however, I do not know $n$ in advance. I thought I could do this using ``Apply,'' namely:
Apply[Sum,Join[{f[Table[Subscript[m,a],{a,1,n}]]},Table[{Subscript[m,a],1,k[[a]]},{a,1,n}]]]
However, I'm running into the following problem. The function $f$ is getting called only once, at the argument ``$\{m_a\}$'', ie, before assigning them the numerical values being summed over. If the function requires numerical inputs, this won't run properly. However, if I write the corresponding Sum by hand (ie, in cases where I know in advance what $n$ is), then $f$ is called for each term in the sum, and there is no problem. How can I make this sum behave as I'd like for arbitrary $n$?
