function best = find_best_n(v)
%v should be a vector of positive integers in nonincreasing order, with
%length at least 2.
%k will be the value occurring in v that minimizes the sum of all
%occurrences of k.  In case of a tie, the larger k is used, unless the
%smaller k is 1, in which case 1 is used.
%The answer is a structure, with fields num, first, last, and total.

best.total = sum(v) + 1;
l = length(v);
i = 1;
while i <= l
    j = i;
    c = v(i);
    while j < l && v(j + 1) == c
        j = j + 1;
    end
    t = c*(j - i + 1);
    if t < best.total || (c == 1 && t == best.total)
        best.total = t;
        best.num = c;
        best.first = i;
        best.last = j;
    end
    i = j + 1;
end