Samuel Yates began, and this site continues, a database of the largest known primes. Primes in that database are assigned a proof-code to show who should be credited with the discovery as well as what programs and projects they used. (Discoverers have one prover-entry, but may have many proof-codes because they use a variety of programs...)
This page provides data on L2521, one of those codes.
Code name (*): L2521 Persons (*): 1 (counting humans only) Projects (*): 1 (counting projects only) Display (HTML): Matillek, PSieve, Srsieve, PrimeGrid, LLR Number of primes: total 18 Unverified Primes: 0 (prime table entries marked 'Composite','Untested', or 'InProcess') Score for Primes (*): total 45.8180
Below is additional information about this entry.
Display (text): Matillek, PSieve, Srsieve, PrimeGrid, LLR Display (short): Matillek Database id: 6037 (do not use this database id, it is subject to change) Proof program: LLR Entry last modified: 2020-10-30 17:50:17