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kruoli 2022-04-04 14:06

[QUOTE=storm5510;603269]This is for M7363 which does not appear in any database I can find.[/QUOTE]

There are already some factors of this number noted in [URL="http://factordb.com/index.php?query=2%5E7363-1"]FactorDB[/URL].

mrh 2022-04-04 14:39

This is a nice one:

[M]M113334241[/M] has a 112.193-bit (34-digit) factor: [url=https://www.mersenne.ca/M113334241]5936815441525476391128324308118983[/url] (P-1,B1=551000,B2=21185000)

storm5510 2022-04-04 16:00

[QUOTE=James Heinrich;603270]7363 is not prime, therefore it's not a Mersenne number.[/QUOTE]

Of course it's not prime. All the ECM exponents in the GIMPS database with found factors are not prime either. That section should not exist.

[U]Edit[/U]: I think you meant to say it is not a natural prime. Without the "2^" and "-1" it has two factors. 37 and 199.

ATH 2022-04-04 16:43

[QUOTE=storm5510;603282]Of course it's not prime. All the ECM exponents in the GIMPS database with found factors are not prime either. That section should not exist.

[U]Edit[/U]: I think you meant to say it is not a natural prime. Without the "2^" and "-1" it has two factors. 37 and 199.[/QUOTE]

7363 itself is not prime: 7363 = 37*199.

It IS still a Mersenne Number which are all 2[SUP]n[/SUP]-1 for integer n: [url]https://mathworld.wolfram.com/MersenneNumber.html[/url]

BUT it is not a Mersenne Number that GIMPS cares about, since only those with prime exponents have a chance to be a Mersenne Prime, that is why it is not in the databases.
[url]https://www.mersenne.org/report_exponent/?exp_lo=7300&exp_hi=7400&text=1[/url]

kruoli 2022-04-05 09:03

Finally got my first Top 10 P-1 factor! :toot:
[M]M239119[/M] has a 157.217-bit (48-digit) factor: [url=https://www.mersenne.ca/M239119]212381331667662033847003656413805352059577410799[/url] (P-1,B1=30000000,B2=10120247026890)
k = 3 × 71 × 5,573 × 79,999 × 830,887 × 1,653,749 × 5,047,213 × 674,304,195,209

James Heinrich 2022-04-05 13:43

[QUOTE=kruoli;603319]Finally got my first Top 10 P-1 factor! :toot:[/QUOTE]Congrats!
Your new factor coincidentally also pushes my best-ever result out of the top-200 :ermm:

masser 2022-04-05 17:52

[QUOTE=kruoli;603319]Finally got my first Top 10 P-1 factor! :toot:
[M]M239119[/M] has a 157.217-bit (48-digit) factor: [url=https://www.mersenne.ca/M239119]212381331667662033847003656413805352059577410799[/url] (P-1,B1=30000000,B2=10120247026890)
k = 3 × 71 × 5,573 × 79,999 × 830,887 × 1,653,749 × 5,047,213 × 674,304,195,209[/QUOTE]

Excellent find!

storm5510 2022-04-08 00:05

P-1 auto-assigned by PrimeNet. [I]Prime95 v29.8 B6[/I]

M113476799: Factor: 435875148110816983338962773598903 / (P-1, B1=515000, B2=8368750)

James Heinrich 2022-04-08 02:32

[QUOTE=storm5510;603499]Prime95 v29.8 B6[/QUOTE]Why so old?

storm5510 2022-04-08 16:44

[QUOTE=James Heinrich;603502]Why so old?[/QUOTE]

I am glad you ask this question. On my older systems, 29.x outperforms 30.x. I never run PRP's or certification work. If I don't use it, then I don't need the capability. I sometimes use a 6.x version of [I]gpuOwl[/I] for P-1's, but it is not self-tending like [I]Prime95[/I] is. It is one less thing I have to keep up with.

James Heinrich 2022-04-08 17:15

[QUOTE=storm5510;603541]On my older systems, 29.x outperforms 30.x[/QUOTE]I can't comment to other worktypes, but this is absolutely untrue for P-1. v30.8 has made absolutely huge gains in P-1 performance. Do not judge it by how fast it runs, but by the bounds and probability it can achieve. Please don't do P-1 badly, you'll miss factors unnecessarily and (if done badly enough) people may need to re-do your work, which is the definition of inefficient.


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