#include <iostream>

using namespace std;

int main() {
    int k, sum;
    while (cin >> k) {
        if (k == 0) break;
        sum = 0;
        for (int i = 0; i < k * (k-1) / 2; i++) {
            int t; cin >> t;
            sum += t;
        }
        cout << sum / (k-1) << endl;
    }
    return 0;
}