finally got it!

see last comment :-), kata will be withdrawn

That's hard, I never thougth to search the internet if anybody already had this idea :-), but you're right, with this information this kata makes no sence and I will withdraw it.

Thanks for your feedback!

The tests do not contain test cases with leading 0s, and it's unclear what should be expected from them, or whether they will be tested.

(Note that in the other regex divisibility katas, this case is usually tested.)

Hi, thanks for your input - added an additional line to explain what the tests are doing, hope that matches you point

Hi, thanks for your input - class name corrected

Hi, thanks for your input - randomized tests added

Missing randomized tests.

Test suite class is called "BinaryRegexpTest".

Test failure messages should be more descriptive.

Great Kata, took me a long time to figure out how to solve until I found something about DFA and regular expressions, but I learned a lot!

thanks for reminding me of my oversight!

In my opinion the character restrict was amazing since it obligates you to refactor the code, but the oneliner is just awful to read.
Thats why most of the solutions aren't voted at all.
Consider keeping the char limit and removing the one liner rule.
Otherwise awesome Kata, love it!