# include <stdio.h>
int N,i,ap[50001],k,v,max,j;
int main(){
  freopen("economie.in", "r", stdin);
  freopen("economie.out", "w", stdout);
  scanf("%d",&N);
  for (i=1;i<=N;++i){
	scanf("%d",&v);
	if (v>max) max=v;
	ap[v]++;
     }
  k=0;
  for (i=1;i<max;i++)
    if (ap[i]){ k++;
      for (j=i+i;j<=max;j+=i)
	    ap[j]=0;
     }
  printf("%d\n",k);
  for (i=1;i<=max;i++)
    if (ap[i])printf("%d ",i);
  return 0;
}