#include <stdio.h>
#include <stdlib.h>

int main(void) 
{
	int k;
	int i;
	int sum, record;

	while (scanf("%d", &k), k != 0) {
		sum = 0;
		
		for (i = 0; i < (k * (k - 1) / 2); i++) {
			scanf(" %d", &record);
			sum += record;
		}
		printf("%d\n", sum / (k - 1));
	}
	return 0;
}