#include<iostream>
using namespace std;

int main() {
  int k,l;
  int p = 0;
  int i =0;
  int a[10000];
  while(1){
  cin >> k;
  l = k*(k-1)/2;
  if(k==0){break;}
  for(i=0;i<l;i++){
    cin >> a[i];
    p += a[i];
  }
  cout << p/(k-1)<<endl;
  p =0;
  }
    return 0;
}

