// Aizu Vol-10 1027: A Piece of Cake
// 2017.8.17 bal4u@uu

#include <stdio.h>

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