2 · 193145605 + 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.

This prime's information:

Description:2 · 193145605 + 1
Verification status (*):Proven
Official Comment (*):Divides Phi(1931^45605,2)
Proof-code(s): (*):g404 : Taniguchi, Proth.exe
Decimal Digits:149849   (log10 is 149848.4016257)
Rank (*):41224 (digit rank is 1)
Entrance Rank (*):1072
Currently on list? (*):no
Submitted:9/6/2007 09:11:53 UTC
Last modified:3/11/2023 15:54:10 UTC
Database id:82137
Status Flags:none
Score (*):40.7998 (normalized score 0.0154)

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.
Divides Phi (archivable *)
Prime on list: no, rank 62
Subcategory: "Divides Phi"
(archival tag id 187405, tag last modified 2023-03-11 15:53:59)

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_id82137
person_id9
machineRedHat P4 P4
whatprime
notesCommand: /home/caldwell/client/pfgw -t -q"2*1931^45605+1" 2>&1 PFGW Version 20031027.x86_Dev (Beta 'caveat utilitor') [FFT v22.13 w/P4] Primality testing 2*1931^45605+1 [N-1, Brillhart-Lehmer-Selfridge] Running N-1 test using base 5 Using SSE2 FFT Adjusting authentication level by 1 for PRIMALITY PROOF Reduced from FFT(65536,20) to FFT(65536,19) Reduced from FFT(65536,19) to FFT(65536,18) Reduced from FFT(65536,18) to FFT(65536,17) Reduced from FFT(65536,17) to FFT(65536,16) 995580 bit request FFT size=(65536,16) Calling Brillhart-Lehmer-Selfridge with factored part 100.00% 2*1931^45605+1 is prime! (-1228.1573s+0.0300s) [Elapsed time: 52.51 minutes]
modified2020-07-07 22:30:40
created2007-09-06 09:14:58
id93394

fieldvalue
prime_id82137
person_id9
machineRedHat P4 P4
whattrial_divided
notesCommand: /home/caldwell/client/TrialDiv/TrialDiv -q 2 1931 45605 1 2>&1 [Elapsed time: 8.299 seconds]
modified2020-07-07 22:30:40
created2007-09-06 09:22:02
id93395

Query times: 0.0002 seconds to select prime, 0.0003 seconds to seek comments.
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