#include<stdio.h>
#define NUM 100
int main()
{
  int K;
  int c[NUM];
  int i;
  int sum;
  while(scanf("%d",&K), K!=0){
    sum=0;
    for(i=0; i<K*(K-1)/2; i++){
      scanf("%d",&c[0]);
      sum+=c[0];
    }
    printf("%d\n", sum/(K-1));
  }
  return 0;
}