#include<stdio.h>
int main()
{
	int n,i,z=0,j,a=0,b=0;
	scanf("%d",&n);
	for(i=2;z<=n;i++)
	{
	   for(j=2;j<=i/2;j++)
	      {if(i%j==0) {a++;break;}}
	   if(a==0)
	   {
	    z+=i;
	    if(z<=n)
	   	{
		printf("%d\n",i);
	   	b++;
	        }
	   }
        }
	printf("%d",b);
	return 0;	
}