https://files.catbox.moe/kjvjz5.pngYou'll notice that most of the arms have 0 primes. That's because this setup has 12 arms, and 8 of the arms are all divisible by either 2 or 3. Will test out other radial values to see if anything cool pops up tomorrow.
Edit: Tested some other arm counts, and it's a really interesting. If the number of arms is prime, that arm (say 7 arms, arm #7) only has a single prime. All other arms are smattered with them. Composite numbers really cut a lot of arms out of the picture, depending on what the factors are, those arms and their multiples will have no primes.