- Michael Bell wrote:

> I think it would be useful if there was a list of PRP's

Well Andy Steward has *oodles* of such animals...

> with over 15 or 20% of either N-1 or N+1 factored

> (or maybe 3*F1+F2>=.6 or so). This would then

> make a list of primes that it may actually be practical

> to prove in the not to distant future.

> Any volunteers for hosting a page?

David - PS: My personal gigantic bete noire is Phi(2521,9926),

with 10072 digits, and N-1 347 digits short of BLS.

As Gollum said, we hates it.... David - Guys,

Primeform gives the following as PRP

6*k*(2^n - 1 - k ) + 2^n - 1, with n = 4497, k = 8939.

digit number = 13400.

A beginner in this business, I would like confirmation of this result from

someone.

Thank you.

Peter Lesala.

-----Original Message-----

From: Henri LIFCHITZ <HLifchitz@...>

To: Primes List <PrimeNumbers@yahoogroups.com>

Date: Friday, April 20, 2001 10:42 PM

Subject: [PrimeNumbers] PRP Top 50 has become PRP Top 100

>Hello all,

100.

>

>By popular demand, I have decided to extend the PRP Top 50 to a PRP Top

>(see http://www.primes.fr.st or

http://ourworld.compuserve.com/homepages/hlifchitz/ )

>For convenience reasons, only the first 50 records will keep a specific

page.

>

digits).

>Please continue sending me new probable primes (but larger than 12000

>

>Happy hunting,

>

>Henri

>

>

>[Non-text portions of this message have been removed]

>

>

>Unsubscribe by an email to: primenumbers-unsubscribe@egroups.com

>The Prime Pages : http://www.primepages.org

>

>

>

>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

>

>

> - In a message dated 18/05/2001 14:29:21 GMT Daylight Time,

mohales@... writes:

> Primeform gives the following as PRP

Hi Peter,

> 6*k*(2^n - 1 - k ) + 2^n - 1, with n = 4497, k = 8939.

> digit number = 13400.

> A beginner in this business, I would like confirmation of this result from

> someone.

> Thank you.

> Peter Lesala.

Something must be wrong with your expression as (if we do the substitutions

for n and k) PFGW says:-

6*8939*(2^4497-1-8939)+2^4497-1 has factors: 7

Want to double-check it?

Mike Oakes - Hi Mike,

There is an error in the value of n = 4497, the value should be n = 44497.

Thanks for the quick response.

Peter.

-----Original Message-----

From: Mikeoakes2@... <Mikeoakes2@...>

To: mohales@... <mohales@...>

Cc: PrimeNumbers@yahoogroups.com <PrimeNumbers@yahoogroups.com>

Date: Friday, May 18, 2001 10:03 PM

Subject: Re: [PrimeNumbers] PRP Top 50 has become PRP Top 100

In a message dated 18/05/2001 14:29:21 GMT Daylight Time,

mohales@... writes:

> Primeform gives the following as PRP

Hi Peter,

> 6*k*(2^n - 1 - k ) + 2^n - 1, with n = 4497, k = 8939.

> digit number = 13400.

> A beginner in this business, I would like confirmation of this result from

> someone.

> Thank you.

> Peter Lesala.

Something must be wrong with your expression as (if we do the substitutions

for n and k) PFGW says:-

6*8939*(2^4497-1-8939)+2^4497-1 has factors: 7

Want to double-check it?

Mike Oakes