#include<stdio.h>
FILE *f1,*f2;
int main()
{long int n,a,b,nr=1,x,y;
f1=fopen("fractii.in","r");
fscanf(f1,"%li",&n);
fclose(f1);
nr=(((n/2)+(n%2))*2)+(2*n-1);
for(a=3;a<=n-1;a=a+2)
for(b=a+2;b<=n;b+=2)
{x=a;
 y=b;
while(x!=y)
if(x>y) x-=y;
else y-=x;
if(x==1) nr+=2;}
f2=fopen("fractii.out","w");
fprintf(f2,"%li",nr);
fclose(f2);
return 0;
}