406^49-1

  Henrik Olsen announces the complete factorization of the number
N=(406^49-1)/(406^7-1) from The Expanded Cunningham Table by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = 1471 * c107

where c107 is a 107 digit composite number given by

  c107 = 24574276332525990781479117675191326947192587137942214268789447884176550832506260207124800298910864329640127

The two polynomials used were

        X^6 + X^5 + X^4 + X^3 + X^2 + X + 1 and
        X - 406^7

with common root 406^7 (mod N).

  The region sieved was b < 164000 and |a| < 262144.
A factorbase size of 100000 and large prime bound of
20M was used for both polynomials.
  A total of 1835134 relations was collected forming
a 324796 x 334993 matrix.
 
  The linear algebra stage took 5.1 CPU hours on a
375MHz Celeron using about ~53M of memory, the square
root stage took 11.5 minutes and found the factorisation
in the first dependency checked.

  On Apr. 27, 2000 it was found that c107 = p48 * p59

  p48 = 559790386053611989431518069444976939844674216869

  p59 = 43899068195452135545127148318307431824928903222316367560083

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