Loading ...
Sorry, an error occurred while loading the content.
 

RE: [PrimeNumbers] Re: Naive question on 2^1896-1

Expand Messages
  • Kevin Acres
    ... From: elevensmooth [mailto:elevensmooth@yahoo.com] Sent: 12 June 2007 22:57 To: primenumbers@yahoogroups.com Subject: [PrimeNumbers] Re: Naive question on
    Message 1 of 6 , Jun 12, 2007
      -----Original Message-----
      From: elevensmooth [mailto:elevensmooth@...]
      Sent: 12 June 2007 22:57
      To: primenumbers@yahoogroups.com
      Subject: [PrimeNumbers] Re: Naive question on 2^1896-1

      --- In primenumbers@yahoogroups.com, "Kevin" <research@...> wrote:
      >
      > I'm trying to factor the last part of 2^1896-1 or:
      >
      > 72009645598802661741572237135153453757864421072572019369424603012486080
      > 97428061518078682794754267412326389601722982929011560986986540564455161
      > 820809601187482593072913719887735073


      > Do you just want the factors, or do you want to learn how to find the
      > factors?

      Hi,

      The question arises from the results of a program I have that diverged from
      the Wieferich search.

      Basically it finds composite Mersenne numbers and a large composite or prime
      (if you're lucky) that divides it.

      A better example than the previous one is where the program output shows:

      2869070461631637574244868351418889546260799144254581951743734382009219393441
      76261145611475682317574468979232833614978133229351

      divides 2^19071324012257094604424955-1

      Which isn't much of a find since the above number actually divides 2^795-1.

      So basically an hours running throws up a lot of large primes, it's just
      unfortunate that nearly all already exist in lowM.txt or are trivially found
      on Alpertron.

      The premise is that it's very easy to produce thousands of large primes or
      composites that divide a range of Mersenne numbers. What isn't easy is to
      find a prime that isn't already known. Rather than attempt to factor a
      specific number it produces a number that it knows will factor some Mersenne
      number.

      Still, I'll spend a while tuning the program and see if anything new pops
      up.

      Kevin.
    • N.L.
      Hello, I have found in few seconds with my program: 2^1896 have prime factor 201487636602438195784363 I don t know, this factor are known ? regards
      Message 2 of 6 , Jun 13, 2007
        Hello,
        I have found in few seconds with my program:

        2^1896 have prime factor 201487636602438195784363

        I don't know, this factor are known ?

        regards

        __________________________________________________
        Do You Yahoo!?
        Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails.
        http://mail.yahoo.com
      • elevensmooth
        ... All factors of 2^1896-1 are known. The simplest way to check that is to use the Alpertron Java factoring applet at http://www.alpertron.com.ar/ECM.HTM
        Message 3 of 6 , Jun 13, 2007
          --- In primenumbers@yahoogroups.com, "N.L." <nluhn@...> wrote:

          > 2^1896 have prime factor 201487636602438195784363
          >
          > I don't know, this factor are known ?

          All factors of 2^1896-1 are known. The simplest way to check that is
          to use the Alpertron Java factoring applet at
          http://www.alpertron.com.ar/ECM.HTM

          William
          Poohbah of OddPerfect.org
        Your message has been successfully submitted and would be delivered to recipients shortly.