#include<fstream>      
using namespace std;      
const int N=1000000;   
int main()      
{      
    ifstream in("fractii.in");      
    ofstream out("fractii.out");      
    int c[N]={0};   
    long long int a[100],n,i,j,x,l=1,ok,nr=0;      
    in>>n;   
    for (i=2;i*i<=n;i++)   
        if (c[i]==0)   
        {a[l]=i;   
        l++;   
        for (j=i+i;j<=n;j=j+i)   
        c[j]=1;}   
    for (i=1;i<=n;i++)   
    for (j=1;j<i;j++)   
    {ok=0;   
    for (x=1;x<=n;x++)   
        if (i%c[x]==0 && j%c[x]==0) ok++;   
    if (ok==0) nr++;}   
    out<<nr*2+1;   
    in.close();      
    out.close();      
    return 0;      
}