#include<fstream.h>

long long j,n,i,x[10000],s=0;
int cmmdc(int a,int b)
{while(a!=b)
{if(a>b)a-=b;
       else b-=a; }
       return a;
}

int main()
{
ifstream f("fractii.in");
ofstream g("fractii.out");
while(f>>n)
{
x[1]=2*n-1;
s=0;
for(i=2;i<=n;i++)
 {x[i]=0;
 for(j=i;j<=n;j++)
  if(cmmdc(i,j)==1)x[i]+=2;



  s+=x[i];}
  g<<s+x[1]<<"\n";}
return 0;
}