#include<stdio.h>
#include<iostream.h>
#include<math.h>
int main()
{long n,sol,p,i,k,r,var,v[30000],ok,j,max;
FILE *f=fopen("fractii.in","r");
FILE *g=fopen("fractii.out","w");
fscanf(f,"%ld",&n); p=1; v[1]=2;
for (i=3;i<=n;i++) {ok=1;
		  for (j=2;j<=sqrt(n);j++) if (i%j==0) {ok=0; break;}
		  if (ok==1) {p++; v[p]=i;}}
sol=n;
if (n%2==0) sol+=n/2;
else sol+=n/2+1;
for (i=3;i<=n;i++)
	{k=n-1;   r=1;
	while (v[r]<i)
	      {if(i%v[r]==0)
			{  max=1;
			var=v[r];
			while (var<=n) {var=var*max;max++; if (var!=i&&var<=n) k--;}}
	      r++;}
	sol+=k;}
fprintf(g,"%ld",sol); cout<<sol;
fclose(f);
fclose(g);
return 0;}