Sierpinski/Riesel Base 5
(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)

project 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.)

p187, p188, p196, p201, p202 ... ... L3528, L3849, L3869, L3903, L3904
E-mail address: (e-mail address unpublished)
Web page:
Username: SR5 (entry created on 06/04/2005)
Database id:768 (entry last modified on 06/28/2014)
Active primes:on current list: 19, rank by number 8
Total primes: number ever on any list: 157.5
Production score: for current list 48 (normalized: 154), total 49.1183, rank by score 9
Largest prime: 154222 · 52091432 + 1 ‏(‎1461854 digits) via code L3523 on 11/10/2015
Most recent: 154222 · 52091432 + 1 ‏(‎1461854 digits) via code L3523 on 11/10/2015
Entrance Rank: mean 151.92 (minimum 51, maximum 236)

Descriptive Data: (report abuse)
This project is searching for a prime of the form k*5^n-1 for each even k less than 346802, to prove that 346802 is the smallest even base five Riesel number, and k*5^n+1 for each even k less than 159986 to prove that 159986 is the smallest even base five Sierpinski number. The original instigator of this project was Robert Smith who started it all with a post in the on 28 Sep 04.

I administer Sierpinski/Riesel Base 5 and I would like to
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Surname: SierpinskiRiesel (used for alphabetizing and in codes)
Unverified primes are omitted from counts and lists until verification completed.