#include<bits/stdc++.h>
#define file(F) freopen(#F".in","r",stdin),freopen(#F".out","w",stdout)
#define lowbit(x) ((x)&-(x))
#define ALL(x) (x).begin(),(x).end()
#define debug(...) fprintf(stderr,__VA_ARGS__)
#define popc(x) (__builtin_popcountll((x)))
#define abs(x) ((x)>=0?(x):-(x))
using namespace std;
using ll=long long;
using uint=uint32_t;
namespace asnown {
using i32=int32_t; using u32=uint32_t;
using i64=int64_t; using u64=uint64_t;
using i128=__int128_t; using u128=__uint128_t; };
template<typename T>
inline bool Max(T &x,T y) { return std::less<T>()(x,y)&&(x=y,true); }
template<typename T>
inline bool Min(T &x,T y) { return std::less<T>()(y,x)&&(x=y,true); }
void Solve();
ll gcd(ll a,ll b) {
   if(b) while(b^=a^=b^=a%=b);
   return a;
}
signed main() {
#ifndef ONLINE_JUDGE
#endif
   cin.tie(nullptr)->sync_with_stdio(false);
   Solve();
}
void Solve() {
   ll n; cin>>n;
   if(n==1) return void(puts("1\n1"));
   vector<ll> ans{1,2};
   ll lst=2;
   for(ll i=2;;)
      if(gcd(i+1,lst)!=1) {
         if(i*(i+2)>n) break;
         ans.emplace_back(i*(i+2));
         i+=2;
      } else {
         if(i*(i+1)>n) break;
         ans.emplace_back(i*(i+1));
         i++;
      }
   printf("%d\n",(int)ans.size());
   for(auto x:ans) printf("%d ",x); puts("");
}