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#include<fstream>
#include<iostream>
#include<cmath>
#include<vector>
using namespace std;
ifstream cin("fractii.in");
ofstream cout("fractii.out");
bool prim(int n)
{
int c=0;
for(int i=1;i*i<=n;i++)
{
if(n%i==0){c++;}
if(c>1){return false;}
}
return true;
}
int fractii(int n)
{
vector<int> v;
int p,j,i,w1,s=0,w=0;
for( i=2;i<=n;i++)
{
for( j=2;j<=i;j++)
{
if(prim(j)==1 && i%j==0)
{
w+=n/j;
v.push_back(j);
}
}
for(int j2=0;j2<v.size()-1;j2++)
{
for(int j3=j2+1;j3<v.size();j3++)
{
s+=(n/(v[j2]*v[j3]));
}
}
v.erase(v.begin(),v.end());
}
w1=n*n-w+s;
return w1;
}
main()
{
int n;
cin>>n;
cout<<fractii(n);
}