Here you go
1- Enter how many numbers you want
2- Enter the width you need
3- Hit 'Generate'
4- Hit 'Download'
Even though this code doesnt exactly do what you want (All N digit numbers), it will give you what you want if you configure it properly. Mind you, it also doesn't check whether your parameters are valid, so make sure they are (ie: 3 digit, 10000 numbers will break your browser :-))