#include <iostream>
using namespace std;

int main() {
  while(1) {
    int K;
    cin >> K;
    if(K == 0) break;

    int num = K*(K-1)/2;
    int temp = 0;
    for(int i = 0; i < num; i++) {
      int in;
      cin >> in;
      temp += in;
    }

    if(K == 1) cout << temp << endl;
    else       cout << temp / (K - 1) << endl;
  }
  return 0;
}