On 7 December 2021, 14:48:06 UTC, PrimeGrid’s Sierpinski/Riesel Base 5 Problem project eliminated k=273662 by finding the mega prime:
The prime is 2,441,715 digits long and enters Chris Caldwell's “The Largest Known Primes Database” ranked 97th overall. 60 k’s now remain in the Riesel Base 5 problem.
The discovery was made by Lukas Plätz (Lukas) of Germany using an AMD Ryzen 7 3700X 8-Core Processor with 16GB RAM, running Linux Mint. This computer took about 2 hours, 57 minutes to complete the prp test using LLR2.
The prime was verified on 8 December 2021, 09:52 UTC, by an AMD Ryzen 9 5900X 12-Core Processor with 64GB RAM, running Linux Mint. This computer took about 15 hours and 49 minutes to complete the primality test using LLR2.
For more details, please see the official announcement.