#include <fstream.h>
long a[50004],n,S;
void citire(){
ifstream fin("economie.in");
fin>>n;
long x;
for (long i=0;i<n;i++) {
      fin>>x;
      a[x]=1;}
fin.close();
}

void numarare(){
for (long i=0;i<=500002;i++)
   if (a[i]==1){
      S++;
      long m=i,c=2;
      while (m*c<=50002){
	  a[m*c]=0;
	  c++;}
   }
}
int main(){
ofstream fout("economie.out");
citire();
numarare();
fout<<S<<"\n";
for (long i=0;i<500001;i++)
   if (a[i]==1)
       fout<<i<<" ";
fout<<"\n";
fout.close();
return 0;
}