#include <stdio.h>
int n,i,j,cnt;

int cmmdc(int x, int y)
{
    int z;
    while(y!=0)
    {
        z=x%y;
        x=y;
        y=z;
    }
    return x;
}

int main()
{
    freopen("fractii.in","r",stdin);
    freopen("fractii.out","w",stdout);
    scanf("%d",&n);
    cnt=n;
    for(i=2;i<=n;i++)
        for(j=1;j<=n;j++)
            if(cmmdc(i,j)==1) cnt++;
    printf("%d",cnt);
    return 0;
}