#include <stdio.h>
#include <stdbool.h>
#define MAX 100001
bool isPrime[MAX] = {0};
int main(void)
{
    int n;
    scanf("%d",&n);
    
    int i, j;
    for (i = 2; i*i <= MAX; i++)
        if (!isPrime[i])
            for (j = i*2; j <= MAX; j += i)
                isPrime[j] = 1;
                
    int total, sum;
        for (i = 2, total = 0; i <= n; i++)
            if (isPrime[i] == 0)
            {
            	sum += i;
            	if (sum <= n)
    			{
    				printf("%d\n",i);
    	        	total++;
            	}
            	else 
            		break;
            }
        printf("%d",total);
        
    return 0;
}