## Re: Computational prime projects

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• ... [...] ... I m working in making a Java applet to factor as fast as possible, so it can be used by the general people on Internet. I implemented the
Message 1 of 21 , Mar 1, 2002
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> We count 351 members on this prime numbers list at the moment.
> I was wondering how many and what prime project(s) they follow
> at present.
[...]
> I'm really curious about what all the members of this list are
> hunting for *at the very moment*. The number of projects alone
> should be immense, but the kind of projects might surprise us.
>
> Hans
>

I'm working in making a Java applet to factor as fast as possible, so
it can be used by the general people on Internet. I implemented the
algorithms ECM and SIQS.

http://www.alpertron.com.ar/ECM.HTM

The source code is available in the same page.

In order to test the applet, I used it to factor a 80-digit composite
= P40 x P41 where:

P40 = (2^132 - 187)/3
P41 = 2^133 - 99

The computation took 2d 8h 57m 34s in a Celeron 566 MHz. The linear
algebra phase, using the Block Lanczos algorithm on a sparse binary
matrix of 26038 x 27379, took only 3m 30s.

There are several other people that are using the applet. See for
example the hunt for the factors of partition numbers P(n) at:

http://www.asahi-net.or.jp/~KC2H-MSM/mathland/part/whatsnew.htm

where Tom Hill is using the applet to find the factors.

Best regards,

Dario Alejandro Alpern
Buenos Aires - Argentina
http://www.alpertron.com.ar/ENGLISH.HTM
• ... For comparison, Satoshi Tomabechi s SIQS took 100 minutes for this c80 ... on a 1 GHz Athlon. Still, it is great that you put your multi-method applet on
Message 2 of 21 , Mar 1, 2002
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Dario Alejandro Alpern wrote:

> P40 = (2^132 - 187)/3
> P41 = 2^133 - 99
> The computation took 2d 8h 57m 34s in a Celeron 566 MHz.

For comparison, Satoshi Tomabechi's SIQS took 100 minutes
for this c80

> P39 = 739315861231459207946328658956357714871
> P41 = 28353250219820203329613565398475280567239
> cputime 1:39:24:52

on a 1 GHz Athlon.

Still, it is great that you put your multi-method applet
on the web, Dario. To combine user-friendliness,
open source, web access, and decent speed is fine