#include <cstdio>

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