383^49-1

  Henrik Olsen announces the complete factorization of the number
N=(383^49-1)/(383^7-1) from The Expanded Cunningham Table by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = 1614836248789 * c97

where c97 is a 97 digit composite number given by

  c97 = 1932947315660178476152470805130470945614\
	2102556691740038796676495197294105210527\
	65063426067965693

The two polynomials used were

        X^6 + X^5 + X^4 + X^3 + X^2 + X + 1 and
        X - 383^7

with common root 383^7 (mod N).

  The region sieved was b < 160000 and |a| < 262144.
A factorbase size of 100000 and large prime bound of
20M was used for both polynomials.
  A total of 1859517 relations was collected forming
a 290423 x 295158 matrix.
 
  The linear algebra stage took 3.6 CPU hours on a
400MHz P-II using about ~40M of memory, the square
root stage took 11.5 minutes and found the factorisation
in the first dependency checked.

  On Apr. 4, 2000 it was found that c97 = p38 * p59

  p38 = 99694463839091965980212586579103217779

  p59 = 19388712684988989122490922164692446941893205863809499215567

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