Geoffrey Reynolds' gcwsieve
(Another of the Prime Pages' resources)
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GIMPS has discovered a new largest known prime number: 282589933-1 (24,862,048 digits)

program A titan, as defined by Samuel Yates, is anyone who has found a titanic prime. This page provides data on those that have found these primes. The data below only reflect on the primes currently on the list. (Many of the terms that are used here are explained on another page.)

L436, L447, L521, p234, p237 ... ... L4779, L4780, L4784, L4972, L4976
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Username: gcwsieve (entry created on 08/08/2007)
Database id:1223 (entry last modified on 09/16/2019)
Program Does *: sieve
Active primes:on current list: 44, rank by number 15
Total primes: number ever on any list: 113
Production score: for current list 52 (normalized: 4110), total 52.3621, rank by score 13
Largest prime: 8508301 · 217016603 - 1 ‏(‎5122515 digits) via code L4784 on 03/22/2018
Most recent: 2805222 · 55610444 + 1 ‏(‎3921539 digits) via code L4972 on 09/03/2019
Entrance Rank: mean 936.61 (minimum 13, maximum 5198)

Descriptive Data: (report abuse)
A sieve for generalised Cullen/Woodall numbers n*b^n+/-1, where n < 2^32, b < 2^32. This sieve requires an existing ABC file (as produced by MultiSieve) with all factors smaller than the greatest exponent n already removed. The algorithm is based on an idea of Harsh Aggarwal, implemented with the help of Mark Rodenkirch.

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Surname: Gcwsieve (used for alphabetizing and in codes)
Unverified primes are omitted from counts and lists until verification completed.