#include <fstream.h>
long a[50004],n,S=0;
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<50002;i++)
   if (a[i]==1){
      S++;
      for (long j=2;j<50002;j++)
	 if (i*j>50002)
	    break;
	 else
	    a[i*j]=0;
   }
}
int main(){
ofstream fout("economie.out");
citire();
numarare();
fout<<S<<"\n";
for (long i=0;i<50001;i++)
   if (a[i]==1)
       fout<<i<<"\n";
fout<<"\n";
fout.close();
return 0;
}