#include <stdio.h>

int gcd(int a, int b) {
    if (b == 0) return a;
    return gcd(b, a % b);
}

int main(){
    FILE *in=fopen("fractii.in", "r");
    
int n, ans;
    fscanf(in, "%f", &n);
    fclose(in);

    for (int i = 1; i <= n; i++)
        for (int j = i; j <= n; j++)
            if (gcd(i, j) == 1) ans++;
  

    FILE *out=fopen("fractii.out", "w");
 
    fprintf(out, "%d", ans );
    fclose(out);
    return 0;
}