Seventeen or Bust Nixes Three Sierpinski Candidates
Craigj0 writes "In just 8 days Seventeen or bust has removed three Sierpinski candidates after people have been trying for years. Seventeen or bust is a distributed attack on the Sierpinski problem. You can find the first two press releases here(1) and here(2), the third is still to come. More information about Sierpinski numbers can be found here. Finally they could always use some more people so join!"
..can be found here (a slightly more detailed explanation than the one at the link the author gives).
This article was only listed under the science section, and not on the main page. The Pi article was presumably determined to have more mass appeal, so was put on the main page as well.
AccountKiller
Here's some info, though the exact construction of the proof isn't give. Apparently, it's possible to prove that for any n, 78557*2^n+1 is divisible by one of a finite (and quite small) number of primes. As to how, ask the guy who proved it...