Geoffrey Reynolds' gcwsieve
(Another of the Prime Pages' resources)
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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 ... ... p357, L3532, L3544, L4472, L4668
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Username: gcwsieve (entry created on 08/08/2007)
Database id:1223 (entry last modified on 08/22/2017)
Program Does *: sieve
Active primes:on current list: 41, rank by number 14
Total primes: number ever on any list: 100
Production score: for current list 50 (normalized: 761), total 50.4033, rank by score 18
Largest prime: 1341174 · 531341174 + 1 ‏(‎2312561 digits) via code L4668 on 08/22/2017
Most recent: 60977 · 14304885 + 1 ‏(‎349443 digits) via code L3532 on 09/26/2017
Entrance Rank: mean 558.34 (minimum 13, maximum 4839)

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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.