GCD

#include <stdio.h>

int GCD(int a, int b){
	int r = 0;
	while(a != 0){
		r = b%a;
		b = a;
		a = r;
	}
	return b;
}

int main(){
	int n;
	while(scanf("%d",&n) != EOF){
		int G = 0;
		if(n == 0)
			break;
		for(int i=1; i<n; i++){
			for(int j=i+1; j<=n; j++)
				G += GCD(i, j);
		}
		printf("%d\n", G);
	}
return 0;
}