#include <stdio.h>
#include <stdlib.h>
int a[1001], n, v[50002], sol[1000], nr;

int cmp(const void *a, const void *b)
{
	return *(int*)a - *(int*)b;
}

int main()
{
	freopen("economie.in","r",stdin);
	freopen("economie,out","w",stdout);
	int i, j;
	scanf("%d",&n);
	for (i = 0; i < n; i++) scanf("%d",&a[i]);

	qsort(a, n, sizeof(a[0]),cmp);

	for (i = 0; i < n; i++)
	{
		if (!v[a[i]])
		{
			sol[++nr] = a[i];
			j = 1;
			while (a[i] * j++ < a[n-1]) v[a[i]*j] = 1;
		}
	}
	printf("%d\n",nr);
	for (i=1; i<=nr; i++) printf("%d\n",sol[i]);
	return 0;
}