#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>

using namespace std;
int sum,i,a,n;
int main(){
    while (scanf("%d",&n),n){
        sum=0;
        for (i=1;i<=(n-1)*n/2;i++){
            scanf("%d",&a);
            sum+=a;
        }
        sum=sum/(n-1);
        printf("%d\n",sum);
    }
    return 0;
}