|So it's not just same numbers, but sequences of numbers that is causing a problem for us|
What you are looking for are called Palindromic numbers.
There are 100, three digit, palindromic numbers from
So in a 5 digit password, you have the possibility of three palindromic numbers appearing.
It may be possible to create some type of checking solution, but I think you will have problems none the less.
You will have a password policy that will need to be remembered, and.
you will have a password exception policy that will need to be remembered.
On top of that, the students will figure out your password policy within about 2 days and then you will never know who is logging in as who.
Once they know all you need do is reverse someones ID to obtain their password,
you have lost all control.
You might want to re-think what your doing.