#include <stdio.h>
int main(){
  int i,j,k,sum;
  scanf("%d",&j);

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