#include <iostream>
#include <vector>
using namespace std;

int main() {
  int k;
  while(cin >> k, k) {
    if(k  == 2) {
      int l;
      cin >> l;
      cout << l << endl;
      continue;
    }
    int ns = k * (k - 1) / 2;
    int total = 0;
    for(int i = 0; i < ns; ++i) {
      int l;
      cin >> l;
      total += l;
    }
    cout << total / (k - 1) << endl;
  }
  return 0;
}