#include <bits/stdc++.h>   using namespace std;   bool prime[1007];   int n;   void sieve() {     for (int i = 4; i <= 1005; i += 2) prime[i] = false, prime[i - 1] = true;     prime[2] = true;     for (int i = 3; i <= 1000; i += 2) {       if (prime[i]) {         for (int j = i * i; j <= 1005; j += i * 2) prime[j] = false;       }     }   }   int main() {     ios::sync_with_stdio(false);     sieve();     scanf( %d , &n);     vector<int> ans;     for (int i = 1; i <= n; i++) {       if (prime[i]) {         int q = 1;         while (q <= n / i) {           q *= i;           ans.push_back(q);         }       }     }     cout << (ans.size()) << endl;     for (int i : ans) {       printf( %d  , i);     }     return 0;   }   