#include<fstream.h>
int main()
	{
		ifstream fin("fractii.in");
		ofstream fout("fractii.out");

		int n, i, j, k, x, m, r;
		fin>>n;

		k=2*n-1;
		for(i=2;i<n;i++)
		  for(j=i+1;j<=n;j++)
			{
			 m=i;
			 x=j;
			 r=x%m;
			 while(r)
				{
					x=m;
					m=r;
					r=x%m;
				}
			 if(m==1)
			  k=k+2;
			}

		fout<<k<<endl;
		return 0;
	}