/*
?? 
?????2??????????5?7?17?19???????????????????
 
???? 
???n?
 
???? 
????n????????????10?????3 5?5 7???????1?????????????????????????empty?
 
???? 
100
 
???? 
3 5
5 7
11 13
17 19
29 31
41 43
59 61
71 73
*/
void main()
{
	int n,i,l=0;
	int sushu(int);
	scanf("%d",&n);
	
	for(i=3;i<=n-2;i+=2)
	{
		if(sushu(i)&&sushu(i+2))
		{
			l++;
			printf("%d %d\n",i,i+2);
		}
	}
	if(l==0)
		printf("empty\n");

}

int sushu(int k)
{
	int p,j,s=0;
		p=sqrt(k);
		for(j=1;j<=p;j+=2)
			if(k%j==0)
				s++;
	if(s==1)  return 1;
	else return 0;
}

