Re: Surrogate factoring demonstrated

From: Prai Jei (pvstownsend_at_zyx-abc.fsnet.co.uk)
Date: 03/05/05

  • Next message: Oliver Betz: "Re: Tiny, simple solution for microcontroller flash loader?"
    Date: Sat, 05 Mar 2005 09:01:17 +0000
    
    

    jstevh@msn.com (or somebody else of the same name) wrote thusly in message
    <1109208919.921737.141190@o13g2000cwo.googlegroups.com>:

    > I think it'd help to show an actual example of surrogate factoring,
    > which of course is a picked example, of a case where it works.
    >
    > M = 105416759748241328380809513
    >
    > T = 260453747714406240508996639168271558799574757802353665
    >
    > and the factorization of T^6, needed by the current algorithm, and
    > calculated by the program by calling itself recursively, until the
    > numbers are small enough to be factored by a list of primes up to 300,
    > is
    >
    >
    > ( 5^6 )( 23^6 )( 61^6 )( 30557^6 )( 137573^6 )( 143881^6 )( 214213^6 )
    > ( 22341796043767^6 )( 12826012523870101^6 )
    >
    > and the program works by iterating through combinations of those
    > factors, with a special equation, and it took it 182,135 main
    > iterations, as there are some other internal iterations which mean a
    > maximum of 728,540 iterations, to get
    >
    > Number factored.
    > Initial Factorization:
    > f_1=247816937
    > f_2=4253815781292790849
    > Now checking its factors...
    >
    > and now the program is STILL running to try and factor f_2 as it is a
    > composite, while f_1 is prime, and that's part of the problem. It's
    > really slow, and doesn't reliably factor.
    >
    > I actually started with a smaller number which didn't factor, so I
    > multiplied it by another large prime, which is part of the second
    > numbers, so I call that technique using a cracking prime, but it's not
    > what I consider a good approach.
    >
    > So you have close to a million iterations to pull out a number that's
    > only a bit over 247 million itself, and that's just not very
    > impressive, but it is far above chance, I think.
    >
    > So that's kind of a quick example of surrogate factoring kind of
    > working. The program is still workong on that second factor, and I
    > don't know if it will factor it or not.
    >
    > There's a lot of theory worked out, but much more to be figured out,
    > given that it doesn't work all the time.
    >
    >
    > James Harris

    Pardon my ignorance of higher mathematics, but that sounds to me very much
    as though you're starting with two numbers a and b, and attempting to show
    some deep magick by which the product ab can be factorised back into a and
    b without actually factorising ab itself but by working with the original a
    and b.

    That of course assumes a and b to be known.

    Now supposing they're not known.................................

    -- 
    Paul Townsend
    Pair them off into threes
    Interchange the alphabetic letter groups to reply
    

  • Next message: Oliver Betz: "Re: Tiny, simple solution for microcontroller flash loader?"

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