Congratulations to Ben Maloney (paleseptember) who discovered the megadigit probable prime 2^4583176+2131. At 1,379,674 decimal digits, this is the first known probable prime with over a million digits. It should soon appear as the new probable prime record at the website of Henri and Renaud Lifchitz, PRP Records: Probable Primes Top 10000. Ben is participating in the project "Five or Bust" - The Dual Sierpinski Problem. This project is outside of PrimeGrid and can be located in the Mersenne forum. For additional information about this project, please see the Welcome to "Five or Bust!" thread. There are only 2 remaining sequences. To help with PRP testing, see this thread. To help with sieving, see this thread.