#include<stdio.h>
int cmmdc(int a,int b)
{while(a!=b)
 {if(a>b)
     a-=b;
  if(b>a)
     b-=a;
 }
 return a;
}
int main()
{FILE *fo,*fc;
 int n=0,i=0,j=0,nr=0;
 fo=fopen("fractii.in","r");
 fscanf(fo,"%d",&n);
 fclose(fo);
 for(i=2;i<=n;i++)
 {for(j=2;j<=n;j++)
  {if(cmmdc(i,j)==1)
      nr++;
  }
 }
 fc=fopen("fractii.out","w");
 fprintf(fc,"%d",nr+2*n-1);
 fclose(fc);
 return 0;
}