#include <fstream.h>
 int main()
{ long i,r,a,n,j,k=0,b;
ifstream f("fractii.in");
ofstream g("fractii.out");
f>>n;
for (i=1;i<=n;i++){a=i;
      for (j=1;j<=n;j++) {
	    b=j;
	    r=a%b;
	    while (r!=0) {
                 a=b;
                   b=r;
	         r=a%b;}
	    if (b==1) {k++;g<<i<<" "<<j<<" ";} }}
g<<k;
f.close();
g.close();
return 0;
}