#include <stdio.h>

int main(void){

	int k, i, sum, ans, tmp;

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