#include <stdio.h>

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