255 · 2161486 + 1

At this site we maintain a list of the 5000 Largest Known Primes which is updated hourly. This list is the most important PrimePages database: a collection of research, records and results all about prime numbers. This page summarizes our information about one of these primes.

Description:255 · 2161486 + 1
Verification status (*):Proven
Official Comment (*):Divides GF(161484,5)
Proof-code(s): (*):g76 : DavalDavis, Proth.exe
Decimal Digits:48615   (log10 is 48614.536419974)
Rank (*):56771 (digit rank is 1)
Entrance Rank (*):131
Currently on list? (*):no
Submitted:6/29/2000 17:35:43 CDT
Last modified:6/29/2000 17:35:43 CDT
Database id:1081
Status Flags:none
Score (*):37.3303 (normalized score 0.0008)

Archival tags:

There are certain forms classed as archivable: these prime may (at times) remain on this list even if they do not make the Top 5000 proper.  Such primes are tracked with archival tags.
Generalized Fermat Divisors (bases 3,5,6,10,12) (archivable *)
Prime on list: no, rank 45, weight 42.871613538137
Subcategory: "Divides GF(*,5)"
(archival tag id 190298, tag last modified 2020-10-29 19:20:16)

Verification data:

The Top 5000 Primes is a list for proven primes only. In order to maintain the integrity of this list, we seek to verify the primality of all submissions.  We are currently unable to check all proofs (ECPP, KP, ...), but we will at least trial divide and PRP check every entry before it is included in the list.
machineWinXP Athlon 1.3GHz
notesPFGW Version 20021217.Win_Dev (Beta 'caveat utilitor') [FFT v22.7 w/P4] Running N-1 test using base 7 Primality testing 255*2^161486+1 [N-1, Brillhart-Lehmer-Selfridge] Calling Brillhart-Lehmer-Selfridge with factored part 100.00% 255*2^161486+1 is prime! (305.669000 seconds)
modified2003-03-25 11:21:54
created2003-01-19 21:49:29

Query times: 0.0005 seconds to select prime, 0.0009 seconds to seek comments.
Printed from the PrimePages <primes.utm.edu> © Chris Caldwell.