#include<stdio.h>

int main(){
    int n,i,j,k,nr,r;
    freopen("fractii.in","r",stdin);
    freopen("fractii.out","w",stdout);

    scanf("%d",&n);

    nr=n;

    for(i=2;i<=n;i++){
        nr++;
        for(j=2;j<=n;j++)
            if(i%j!=0&&j%i!=0)
                nr++;
    }

    printf("%d",nr);
    return 0;
}