#include<stdio.h>
main(){
  int K,sum=0,x,i;
  while(scanf("%d",&K)){
    if(K==0)break;
    sum=0;
    for(i=0;i<K*(K-1)/2;i++){
      scanf("%d",&x);
      sum+=x;
    }
    printf("%d\n",sum/(K-1));
    
  }
}