- Mike Oakes wrote:

> There is a natural cutoff set by the

Don't forget VFYPR. For cases where N^2-1 has good --

> ability of programs like Titanix to prove primality

but not yet BLS -- factorization, VFYPR is more powerful.

Bouk and I and are mounting an attack on the APRCL record,

at 5k+ digits, after 20 days CPUtime spent on ECM,

getting 72 digits short of 3*F1+F2=1. We have good actuarial

reasons for believing that VFYPR will complete

before ECM is likely to cough up another p35.

It would be useful, for cyclotomic PrPs,

like U, V, (2^n+1)/3, repunits, etc,

if folk posted some percentages (as I did) in

http://

ourworld.compuserve.com/homepages/hlifchitz/Henri/fr-us/PrpRec.htm

[too long for one yahoo line, sorry]

David - 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