Problem Statement

Compute the   nth   term of a series,   i.e. the sum of the   n   first terms of the corresponding sequence.
Informally this value, or its limit when   n   tends to infinity, is also called the sum of the series, thus the title of this task. For this task, use:

This approximates the   zeta function   for   S=2,   whose exact value is the solution of the Basel problem.

Let's start with the solution:

sum(S) :-
        findall(L, (between(1,1000,N),L is 1/N^2), Ls),
        sumlist(Ls, S).