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#include <iostream>
#include <cstdlib>
#include <fstream>
using namespace std;
int gcd(int u, int v) {
while ( v != 0) {
int r = u % v;
u = v;
v = r;
}
return u;
}
int f(int n){
int s = 0;
for(int i=1;i<=n;i++)
if(gcd(i,n)==1)
s+=2;
return s;
}
int main()
{
int N=-1, n;
ifstream myfile;
myfile.open ("fractii.in");
myfile >> n;
for(int i=1; i<=n;i++)
N+=f(i);
ofstream f("fractii.out");
f << N;
}