Other primes thread
 

I think I'm starting a thread like in RPS here for non-riesel primes found by NPLB members/special riesel primes found by others.

--nuggetprime

First prime
 

Found 6th largest Generalized Woodall Prime:
91850*19^91850-1 is prime!

This is one of only 3 top-5000 primes found by phil's phrot and the first bigger/top5000 discovery for Geoff's phrot port for linux.

--nuggetprime

[quote=nuggetprime;145557]Found 6th largest Generalized Woodall Prime:
91850*19^91850-1 is prime!

This is one of only 3 top-5000 primes found by phil's phrot and the first bigger/top5000 discovery for Geoff's phrot port for linux.

--nuggetprime[/quote]


Great idea nugget! VERY nice find! It's nice to see primes discovered in other bases.

Nearly breaking Kosmaj's GW record:
146478*19^146478-1 is prime!:banana:(187315 digits)

Now 2nd largest GW.

--nuggetprime

The new world record
 

As you may have already noticed, a few days ago I found the largest known GW prime:
189620*19^189620-1 is prime!:anurag:(242483 digits)

--nuggetprime

[quote=nuggetprime;148242]As you may have already noticed, a few days ago I found the largest known GW prime:
189620*19^189620-1 is prime!:anurag:(242483 digits)

--nuggetprime[/quote]


Tremendous nugget! Way to go! Top of the heap now. :smile:

[URL="http://primes.utm.edu/primes/page.php?id=85789"]5*2^2460482-1[/URL]

[quote=em99010pepe;149860][URL="http://primes.utm.edu/primes/page.php?id=85789"]5*2^2460482-1[/URL][/quote]


So THAT is where Benson has been at all this time!

I guess for a score of 423, it was worth it. That equals about 100 of our n=550K primes! :surprised

It will move him up to #17 on the scores list at top-5000. If you remove the people who have found < 5 primes, he'd be #3!

Benson, can you help push our 1st drive a little? lol


Gary

Something smells extremely fishy about this recent huge submission:

[URL]http://primes.utm.edu/primes/page.php?id=86270[/URL]

First time searcher...huge prime...at or near power-of-10 k and n-value...I've seen this kind of thing before and I'm thinking not! It looks like a "wannabe" prime. But who knows? Stranger things have happened!

I'm putting a slow sore on sieving it to at least P=10G to see if I can save the top-5000 site a little time. I know they do trial factoring before primality testing but I don't know if they sieve. I ran srsieve to P=300M with no factors found and now have it on sr1sieve, which appears will take ~5-10 mins. to build a Legendre symbol table before starting a much faster sieve.

If it turns out to be prime, I'll be the first to retract my first para. here.


Gary

[quote=gd_barnes;159466]Something smells extremely fishy about this recent huge submission:

[URL]http://primes.utm.edu/primes/page.php?id=86270[/URL]

First time searcher...huge prime...at or near power-of-10 k and n-value...I've seen this kind of thing before and I'm thinking not! It looks like a "wannabe" prime. But who knows? Stranger things have happened!

I'm putting a slow sore on sieving it to at least P=10G to see if I can save the top-5000 site a little time. I know they do trial factoring before primality testing but I don't know if they sieve. I ran srsieve to P=300M with no factors found and now have it on sr1sieve, which appears will take ~5-10 mins. to build a Legendre symbol table before starting a much faster sieve.

If it turns out to be prime, I'll be the first to retract my first para. here.


Gary[/quote]


I ended up sieving 100000005*2^10000000-1 to P=25G...no factors found.

I just now saw that the submission was proven composite...no surprise there. See [URL]http://primes.utm.edu/primes/page.php?id=86270[/URL]. Also, another "smaller" submission for 1767766^32768+1 by the same person at [URL]http://primes.utm.edu/primes/page.php?id=86278[/URL] was also proven composite.

It's clear that he did some sieving and then submitted them without primality testing hoping that they were prime. In doing that, he wasted over a day worth of CPU time at the top-5000 site causing the proof of all of our legitimate submissions to slow down greatly. (I observed this.)

Mr. Musatov, you are a bane to the prime-searching community! Put in the CPU time like everyone else! :mad:


Gary

[quote=gd_barnes;159678]I ended up sieving 100000005*2^10000000-1 to P=25G...no factors found.

I just now saw that the submission was proven composite...no surprise there. See [URL]http://primes.utm.edu/primes/page.php?id=86270[/URL]. Also, another "smaller" submission for 1767766^32768+1 by the same person at [URL]http://primes.utm.edu/primes/page.php?id=86278[/URL] was also proven composite.

It's clear that he did some sieving and then submitted them without primality testing hoping that they were prime. In doing that, he wasted over a day worth of CPU time at the top-5000 site causing the proof of all of our legitimate submissions to slow down greatly. (I observed this.)

Mr. Musatov, you are a bane to the prime-searching community! Put in the CPU time like everyone else! :mad:


Gary[/quote]
I think users will get banned at the top-5000 site if they submit too many composite primes. Not sure exactly how many's the limit though.