I wonder how zer0lfsr work

[Deleted user]

if there's only one lfsr, it is not hard to understand how z3 break the encryption.but why when the 3 lfsr combine, it still works? how can z3 do that? What algorithm is used? i would be grateful if you can solve my doubts.

[Pharisaeus]

I believe the proper scientific explanation is the one from Hellman -> https://gist.github.com/hellman/8aceadab98c76d1dd19199b587319fbf

The fact that Z3 can also solve this, suggests that there is some clear relation between the output bit and the state of those 3 registers. I simply asked Z3 to check if there is one, and there was :)