Update: so, after tinkering around with the javascript for a while i figured out that the approach i was using, which was to generate primes using a sieve method and then do prime factorization on all the numbers in n, combining the sets of those factors i haven't seen yet (duplicates notwithstanding) and returning the product thereof... well it craps out around n = 43... so my approach doesn't scale up i guess for some reason. anyway i learned a lot about math messing around with this which is nice since i haven't thought about prime factorization since i was a young lad. thanks for the fun (even though i didn't solve it :P)

Why would my solution fail around n 43? :P