#include<iostream>
#include<fstream>
#define N 1000001
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
long long t,i,j,n,a[10000][10000];
int euclid (int a, int b)
{if(!b)return a;
return euclid(b,a-b*(a/b));
}


int main()
{f>>n;
f.close();
for(i=1;i<=n;i++)
	for(j=i;j<=n;j++)if(euclid(i,j)==1)a[i][j]=a[j][i]=1;

for(i=1;i<=n;i++)
	for(j=1;j<=n;j++)if(a[i][j]==1)t++;
g<<t;
g.close();
return 0;

}