#include <stdio.h>
#include <stdlib.h>
#include<math.h>
int cmmdc(int x, int y) {
    int r;
    while(y) {
    r = x % y;
    x = y;
    y = r;
      }
      return x;
}
    
    
int main()
{         FILE * f;
          FILE * g;
          int i,j,N;
          int k = 1;
          f=fopen("fractii.in", "r");
          g=fopen("fractii.out","w");
          fscanf(f,"%d",&N);
     
for(i=1;i<=N;i++)
               for(j=1;j<=i;j++){
               if(i!=j)
                                 if(cmmdc(i,j)==1)
                                                   k=k+2;
                                                   
                                                   }                
                                                   
                 
  fprintf(g,"%d", k);	
  return 0;
}