#include <stdio.h>

int main(void)
{
    int k;

    while (scanf("%d", &k), k){
        int i;
        int sum = 0;

        for (i = 0; i < k * (k - 1) / 2; i++){
            int c;

            scanf("%d", &c);
            sum += c;
        }
        printf("%d\n", sum / (k - 1));
    }

    return 0;
}