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#include <fstream>
#include <string.h>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int ok[1000001];
int main()
{int n,i,j,r,a,b;
long long s=0;
f>>n;
for(i=2;i*i<=1000000;i++)
{ if(!ok[i])
{
j=2;
while(i*j<=1000000)
ok[i*j]=1,j++;
}
}
for(i=1;i<=n;i++)
for(j=1;j<=n;j++)
if(!ok[i]&&!ok[j]&&i!=j) s++;
else if(!ok[i]&&j%i) s++;
else if(!ok[j]&&i%j) s++;
else{
a=i;
b=j;
r=a%b;
while(r)
a=b,b=r,r=a%b;
if(b==1) s++;
}
g<<s;
}