> Also this would catch those users still using 15.x, which doesn't
> have the same automatic mechanism for intermediate check-ins.
>
> It would also - improperly - catch those of us that can't use the
> automatic networking but whose machines are slower than the estimate
> for some reason. A participant without email access that sends me
> USMail with his data now and then is about to get caught by this for
> an exponent that he's working on; 60 days simply isn't going to be
> enough even though the prediction was for less than 40 days.
Not neccessarily.
What I meant was, if the last date any message was received about an
exponent is more than 4 months ago, reassign it, even if the expected
completion date hasn't yet arrived.
It doesn't seem unreasonable to expect those that have work
outstanding should check in every 2 or 3 months just to say "this
work is still underway".
The current situation is, if a user gets an assignment & drops out
"silently" after 1 day, the assignment does not get reassigned until
60 days after the initial estimated completion date. If I
(stupidly) force a 486 SX 25 to ask for LL tests & get a "big"
exponent, the completion date could be a few decades into the future!
> Also, P-1 factoring, using Factor98, is still useful, there are still
> many exponents under 1000 that noone is working on, and it will work
> on exponents thru 170,000. Reserve exponents for P-1 by sending me
> email; I also have some Factor98 save files for many exponents.
Perhaps you should publicise this a bit...
> (b) an annual prize for the numerically largest factor found during
> each calendar year - though I don't know where the money would come
> from.
>
> Neither do I; I'm still kind of surprised someone is offering money
> for the next Mersenne prime.
I have an idea that this prize could be by subscription. i.e. anyone
can contribute to the work without subscribing (so that those with
moral objections or resident in areas with legal hangups weren't
obliged to enter the "lottery"), but you won't be eligible to win the
prize unless you subscribe. If you got 1000 people to chip in $1 a
year each, the prize would be worthwhile.
> And it would have to be worded very carefully; I can give you lots of
> very large factors quite quickly, including fifteen or more that are
> almost certainly prime but noone has proven to be prime. The largest
> is 9778 digits and would be the largest "hard" prime known by a wide
> margin. Would any of them count? I can likely find almost
> arbitrarily large ones in the future; how about them?
Good point.
Does ECM find only prime factors, or is it just that it is so much
more likely to find factors which are numerically small, so that
factors composed of a product of two or more largish primes are most
unlikely to be discovered without discovering the prime factors?
How do you verify that an arbitary number with ~1000 digits really is
prime? (Let alone a number ten times that length!) ECM seems to be
good for finding primes up to about 50 digits using current hardware
(meaning that the time taken to search for factors much bigger than
50 digits gets prohibitive, even with state-of-the-art hardware.
I think the rules would have to state that the "prize" factor must be
found using one of a set of specific programs, which must supply the
"s number" so that the calculation can be verified.
Just like the Mersenne Prime prize, you could improve your chances of
winning the prize by throwing more processor power in, that is most
of the point of offerring it.
Regards
Brian Beesley
