#include <iostream>

int main(void) 
{
  while (true) {
    int k;
    std::cin >> k;
    if (k == 0) break;
    int num = k * (k - 1) / 2;
    int sum = 0;
    for (int i=0; i < num; i++) {
      int n;
      std::cin >> n;
      sum += n;
    }
    std::cout << sum / (k - 1) << std::endl;
    //std::cout << "sum = " << sum << std::endl;
  }
  
  
  return 0;
}