#include<fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int n,r,a,b,sol,i,j;
int main(){
fin>>n;
sol=0;
for(i=1;i<=n;i++){
    for(j=i+1;j<=n;j++){
            b=i;
            a=j;
        while(b!=0){
            r=a%b;
            a=b;
            b=r;
}
if(a==1){
    sol++;
}
    }
}
fout<<sol*2+1;
return 0;
}