On 22 Apr 00, at 12:41, Dieter Schmitt wrote:
> this 71-bit factor was found by P-1 out of 17 exponents (so far):
>
> [Sat Apr 15 01:47:40 2000]
> P-1 found a factor in stage #1, B1=25000, B2=275000.
> UID: dismit/P233MMX, M4428701 has a factor: 3035629975521900014017
>
> It was found at stage 1 by V20 beta 4. I'd have expected finding
> factors at lower bits first.
All the factors of M4428701 are of the form 2.4428701.k+1, in this
case k = 342722389197408 = 2^5.3.11^2.17.53.251.283.461
Note that all the prime factors of k are (considerably) less than
25000 which is why the factor was found in stage 1. In this case,
running P-1 stage 1 only with B1 = 500 would have sufficed!
> > Well it finally happened to me...., I was double checking an
> exponent in
> > the 5M range, using the beta of V20 and it found a factor! I often
> wondered
> > about how often that happened, anyone have any other hard data?
I've been lucky & found a couple in about 40 runs. (Since I was in
early on the QA trials...) Actually the theoretical chance of finding
a factor with particular B limit values appears to be working out
pretty well. Not surprising really! This chance is printed in the
console window when a P-1 run starts, or resumes after being stopped.
> >
> > 5008021 63 DF 7054282710141713489 10-Apr-00 07:09 gateway
k = 704298435464 = 2^3.13.103.4639.14173
Regards
Brian Beesley
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