787302705 · 256790+1
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At this site we maintain a list of the 5000 Largest Known Primes which is updated hourly. This list is the most important databases at The Prime Pages: a collection of research, records and results all about prime numbers. This page summarizes our information about one of these primes.

This prime's information:

field (help)value
Description:787302705 · 256790+1
Verification status (*):Proven
Official Comment:Cunningham chain 2nd kind (2p-1)
Proof-code(s): (*):g336 : Tornberg, PRP, NewPGen, Proth.exe
Decimal Digits:17105   (log10 is 17104.3895955)
Rank (*):37561 (digit rank is 2)
Entrance Rank (*):21318
Currently on list? (*):no
Submitted:3/13/2005 14:14:36 CDT
Last modified:3/13/2005 14:14:36 CDT
Database id:73724
Status Flags:none
Score (*):34.1024 (normalized score 0.0014)

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.
Cunningham Chains (2nd kind) (archivable class *)
Prime on list: no, rank 6, weight 33.8245659882852
Subcategory: "Cunningham chain 2nd kind (2p-1)"
(archival tag id 192400, tag last modified 2009-11-08 00:20:25)

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.
fieldvalue
prime_id73724
person_id9
machineLinux P4 2.8GHz
whatprime
notesCommand: /home/caldwell/client/pfgw -f -t -q"787302705*2^56790+1" 2>&1
PFGW Version 20031027.x86_Dev (Beta 'caveat utilitor') [FFT v22.13 w/P4]
Primality testing 787302705*2^56790+1 [N-1, Brillhart-Lehmer-Selfridge]
trial factoring to 5128198
Running N-1 test using base 13
Using SSE2 FFT
Adjusting authentication level by 1 for PRIMALITY PROOF
Reduced from FFT(7168,21) to FFT(7168,20)
Reduced from FFT(7168,20) to FFT(7168,19)
Reduced from FFT(7168,19) to FFT(7168,18)
Reduced from FFT(7168,18) to FFT(7168,17)
Reduced from FFT(7168,17) to FFT(7168,16)
113648 bit request FFT size=(7168,16)
Calling Brillhart-Lehmer-Selfridge with factored part 99.95%
787302705*2^56790+1 is prime! (42.8161s+0.0003s)
modified2005-03-29 11:22:33
created2005-03-13 14:23:41
id78739

Query times: 0.0003 seconds to select prime, 0.0004 seconds to seek comments.