#include "bits/stdc++.h"
using namespace std;

#define OO INT_MAX/10
#define PB push_back
#define MP make_pair
#define MOD 1000000007
#define EPS 1e-9
#define endl "\n"
#define all(v) (v).begin(),(v).end()

typedef long long int ll;
typedef pair<int,int> ii;
typedef vector <int>vi;
typedef vector <ii>vii;
typedef vector<vi> vvi;
typedef vector<vii>vvii;

void read()
{
#ifdef OR_WORKSTATION
    freopen("in.in","rt",stdin);
    freopen("outt.out","wt",stdout);
#endif
}

vector<bool>a;
vi primes;
void sieve ()
{
    int n=1500;
    a.assign(n,1);
    a[0]=0;
    a[1]=0;
    for(int i=2;i<1500;i++)
    {
        if(a[i])
        {
            for(int j=i*i;j<n;j+=i)
                a[j]=0;
            primes.PB(i);
        }
        
    }
    
}

int main()
{
    read();
    sieve();
    int n;
    while(cin>>n)
    {
        vi v;
        for(int i=0;i<=169;i++)
        {
            int tmp=primes[i];
            if(tmp>n)
                break;
            int cnt=1;
            while(1)
            {
                tmp=pow(primes[i],cnt++);                
                if(tmp>n)
                    break;
                v.PB(tmp);   
            }
        }
        int l=v.size();
        cout<<l<<endl;
        for(int i=0;i<l;i++)
            cout<<v[i]<<" ";
        cout<<endl;
    }
  
    
}