353^49-1

  Henrik Olsen announces the complete factorization of the number
N=(353^49-1)/(353^7-1) from The Expanded Cunningham Table by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = 197 * 29989 * c101

where c is a 101 digit composite number given by

 c101 = 1718341250600117419285602702532655368898\
	7890327842407104768138947732248471551973\
	066479858419927700639

The two polynomials used were

        X^6 + X^5 + X^4 + X^3 + X^2 + X + 1 and
        X - 353^7

with common root 353^7 (mod N).

  The region sieved was b < 150000 and |a| < 262144.
A factorbase size of 100000 and large prime bound of
20M was used for both polynomials.
  A total of 2038904 relations was collected forming
a 217463 x 233048 matrix.

  The linear algebra stage took 2.7 CPU hours on a
375MHz Celeron using about 45MB of memory, the square
root stage took 11.3 minutes and found the factorisation
in the first dependency checked.

  On May 6, 2000 it was found that c101 = p43 * p58

  p43 = 2812218622150110474776369000327786430499957

  p58 = 6110269084579000700308464012023223393122446287357660367427

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