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

int main(){
  int k,c;
  int i;
  int sum;

  while(cin>>k,k){
    sum=0;
    
    for(i=0;i<(k*(k-1)/2);i++){
      cin>>c;
      sum+=c;
    }
    printf("%d\n",sum/(k-1));
  }
  return 0;
}