Hi, thanks for the response!

I tested your solution, it matches three comma separated numbers, that's half the way :)

But sorry I haven't been clear enough - what I'd like to know is if it's possible to match **directly** following numbers (in the natural ascending order and __not__ like this: 3,5,4).

So there has to be an increment by one for each number in the regex ... somehow!

Do you know what I mean?