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 ... ... L5546, L5551, L5598, L5819, p435
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Username NPLB (entry created on 7/21/2003 01:51:19 UTC)
Database id:518 (entry last modified on 11/2/2023 01:49:47 UTC)
Active primes:on current list: 235, rank by number 4
Total primes: number ever on any list: 4410
Production score: for current list 51 (normalized: 492), total 51.7382, rank by score 8
Largest prime: 333 · 24846958 - 1 ‏(‎1459083 digits) via code L5546 on 5/17/2022 18:06:13 UTC
Most recent: 859 · 22172477 - 1 ‏(‎653984 digits) via code L5819 on 4/9/2024 04:51:22 UTC
Entrance Rank: mean 2924.16 (minimum 303, maximum 4299)

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 n-range than the original PrimeSearch project. This includes mostly top-5000 efforts but from time-to-time can include non-top-5000 and/or double-check efforts.

New searches are currently being conducted for k=300-1001 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. Sieved files are also available for those who like to search their own k's or who like to search for primes offline in a less-automated fashion.

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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