sub isprime{
	($v)=@_;
	for($i=2;$i*$i<=$v;++$i){
		if($v%$i==0){
			return 0;
		}
	}
	return $v>1;
}

$m=<>;
<>;
@c=glob<>;

$b[$m]=1;
for($j=$m;--$j;){
	for(@c){
		if($b[$j+$_] && $a[$j]<$a[$j+$_]+1){
			$b[$j]=1;
			$a[$j]=$a[$j+$_]+1;
		}
	}
	if(isprime$j){
		$s+=$a[$j];
	}
}
($yasui)=sort{$a-$b}@c;
print$s+$m/$yasui|0;