There are two things you need to do. You first need to write a paper, however brief, with a statement and proof of your pattern / test. Then, you can submit it to a journal for publication.
To be honest, I am extremely skeptical about your claim. If there were such an obvious or easy test for primality, somebody probably would have seen it by now and it would be well-known. (We've been looking at primes for thousands of years.)