No Prime Left Behind (formerly: PrimeSearch)


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 reflects on the primes currently on the list. (Many of the terms that are used here are explained on another page.)

g190, g193, g219, g263, g314 ... ... L5551, L5598, L5819, p435, A27
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Username NPLB (entry created on 7/21/2003 01:51:19 UTC)
Database id:518 (entry last modified on 5/14/2024 12:15:28 UTC)
Active primes:on current list: 246, rank by number 3
Total primes: number ever on any list: 4442
Production score: for current list 51 (normalized: 498), total 51.8003, rank by score 8
Largest prime: 333 · 24846958 - 1 ‏(‎1459083 digits) via code L5546 on 5/17/2022 18:06:13 UTC
Most recent: 153 · 22522271 - 1 ‏(‎759282 digits) via code A27 on 7/14/2024 05:32:41 UTC
Entrance Rank: mean 3045.37 (minimum 303, maximum 4693)

Descriptive Data: (report abuse)

The PrimeSearch project was originally created by Michael Hartley to search for primes of the form k*2^n-1 (Riesel primes) for k=300-1001 up to n=600K.

In Jan. 2008, the project was expanded by the "No Prime Left Behind" (NPLB) project at the site. The intent now is to find Riesel primes that have not been found by others (or otherwise left behind) in a much larger k and n-range than the original project. This includes mostly top-5000 efforts but from time-to-time can include non-top-5000 and/or double-check efforts.

Searches are currently being conducted for k<=1001 for 100's of k's at once on many different drives.

Coordinated team drives, automated PRPnet processing, and well-sieved files already available make finding primes very quick and easy for both novices and experienced prime searchers alike.

Surname: NPLB (used for alphabetizing and in codes).
Unverified primes are omitted from counts and lists until verification completed.
I administer No Prime Left Behind (formerly: PrimeSearch) and I would like to
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Printed from the PrimePages <> © Reginald McLean.