#include<stdio.h>
#define NMAX 1000000

long long a[NMAX+1];

long long fractii(int n) {
	if(a[n]!=0) {
		return a[n];
	} else {
		int i;
		long long val = n*n;
		for(i=n;i>=2;i--) {
			val = val - fractii(n/i);
		}
		a[n] = val;
		return val;
	}
}

int main() {
	FILE* fin = fopen("fractii.in", "r");
	int n;
	fscanf(fin, "%d\n", &n);
	fclose(fin);
	
	a[1] = 1;
	long long res = fractii(n);
	
	FILE* fout = fopen("fractii.out", "w");
	fprintf(fout, "%L\n", res);
	fclose(fout);
	return 0;
}