New online applet for factorization

[ET_]

Hi, as many of you recently used Factor, I deployed a server-based application to try and factor exponents above 2³².

The page is here.
It is managed by a DB: just click on the numbers in the "#" column and make k rise
Please feel free to visit and test it

Luigi

[debrouxl]

The correct link seems to be http://www.moregimps.it/mersenne-test

[ET_]

Originally Posted by debrouxl

The correct link seems to be http://www.moregimps.it/mersenne-test

Shat hippens... Oh, well.

Thanks debrouxl...

Luigi

[em99010pepe]

When I click on "#" column it should keep running until it finds a factor, right? Here the applet runs for 2 seconds then stops.

[firejuggler]

quoting from the howto

What happens after you clicked on the link? First of all, a bit of theory. A Mersenne number has form 2p-1, where p is a prime number. Each factor of a Mersenne number has form 2kp+1 where p is the exponent of the number and k is a natural number (1,2,3,4,5---). When you click the link, the program makes a bit of magics and tests about 500,000 successive values of k (well, not exactly... there are some heuristics that lower the number of tests done under 100,000) using a well known algorithm. The values are stored into a database that keeps track of every single click, and updates the state of the search.

the K grow by 500k chunk.
what worry me is that, once the 10-15 first click, the progress seem to stop. Maybe you can increase the number of tested k past 57 bits?

[ET_]

Originally Posted by em99010pepe

When I click on "#" column it should keep running until it finds a factor, right? Here the applet runs for 2 seconds then stops.

No, the applet keeps running until the chunk of 500,000 k is computed, so you can find 1, 2 or even 3 factors on the first run.

Luigi

[ET_]

Originally Posted by firejuggler

quoting from the howto

the K grow by 500k chunk.
what worry me is that, once the 10-15 first click, the progress seem to stop. Maybe you can increase the number of tested k past 57 bits?

There is no upper limit on k. Anyway, with higher k's the increment between 2 batches is less than 0.0001 bits, so you may not notice it.

Luigi

[smh]

Why does it such small batches?

[firejuggler]

34.5850 bits , k=3
35.0000 bits, k= 4
35.3219 bits, k=5
35.8074 bits, k=7
.....
55.3532 bits, k= 5357831
57.0992 bits, k=2^3*7 * 320923
hmmm pm1 would have been a better method there

[ValerieVonck]

I have another issue ... when I click a random number, Firefox always says: 'No factor found' before returning to the startpage

[firejuggler]

thats the normal thing . it does trial divide ... if it does not find a factor, why should it do?