#include <iostream>
using namespace std;

int main() {
  int n;
  int num = 0;
  int w = 0;
  while(cin >> n && n) {
    for(int i = 0; i < n*(n-1)/2; i++) {
      cin >> num;
      w += num;
    }
    cout << w /(n-1) << endl;
    num = 0;
    w = 0;
  }

  return 0;
}