This is what I have been looking for. The only formula I could find that was from a seemingly reliable sources was I = 1/d2 , wherein I = intensity and d = distance.
In other words, some people claim that it follows the inverse square law. This would be for a 'monopole', though. For a dipole it would be I = 1/d3.
If this is true then it's easily solvable, but some sources tell me that it's not exactly true...
Other than that, I don't exactly understand why magnetism follows the inverse square law, but that's for another day.