In a previous post, I gave an informal explanation of the P=NP? problem. In that post, I described both deterministic and nondeterministic Turing machines. A couple of months ago, I decided to implement the deterministic Turing machine in Python.
I also implemented a special deterministic Turing machine that decides whether a given positive integer is divisible by 4, just like the hypothetical Turing machine that I describe in my previous post.
I include a Bash script that tests that implementation. The script inputs every multiple of 4, ranging from 4 to 40, into the Turing machine program. The program passes every test.