#include<stdio.h>
int main()
{
    int N,N1 = 1, N2 = 1, total = 0;
    freopen("fractii.in", "r", stdin);
    freopen("fractii.out", "w", stdout);
    scanf("%d", &N);
    if (N >= 1)
    {
        while (N1 <= N)
         {
         if (N2 > N)
          {
           N1++; N2 = 1;
         if (N1 > N)
                  break;
       }
          if (Prime(N1, N2) == 0)
               total++;
               N2++;
        }
    }
    printf("%d\n", total);
    return 0;
}
int Prime(int a, int b)
        {
            if((a % 2) == 0 && (b % 2) == 0)
            {return 0;}
            else if((a % 3) == 0 && (b % 3) == 0)
            {return 0;}
            else if((a % 5) == 0 && (b % 5) == 0)
            {return 0;}
            else if((a % 7) == 0 && (b % 7) == 0)
            {return 0;}
        }