#include <iostream>
#include<cstdio>
FILE * f=fopen("fractii.in","r");
FILE * g=fopen("fractii.out","w");
using namespace std;
int n;
int gcd(int x,int y)
{
    if(x==y)
        return x;

        if(x>y)
            return gcd(x-y,y);

          return   gcd(x,y-x);

}
int nrp(int k,int f)
{
    int i,s=0;
    for(i=1;i<=f;i++)
    {
        if(gcd(k,i)==1)
            s++;
    }
    return s;
}
int main()
{  int t=0,i;
fscanf(f,"%d",&n);

cout<<gcd(1,5);
 for(i=1;i<=n;i++)
 {
     t=t+nrp(i,n);
 }
 fprintf(g,"%d",t);
return 0;
}