#include <stdio.h>

int main(void)
{
    int m, n, s;
    int i;
    
    while (scanf("%d", &m) && m){
        
        s = 0;
        for(i = 0; i < m * (m - 1) / 2; i++){
            scanf("%d", &n);
            s += n;
        }
        printf("%d\n", s / (m - 1));
    }
    
    return (0);
}