366^49-1

  Henrik Olsen announces the complete factorization of the number
N=(366^49-1)/(366^7-1) from The Expanded Cunningham Table by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = c108

where c108 is a 108 digit composite number given by

 c108 = 4636663584338051684703078758285942497234\
	5157694483277308666744675750356063788146\
	8263592516046027764304651137

The two polynomials used were

        X^6 + X^5 + X^4 + X^3 + X^2 + X + 1 and
        X - 366^7

with common root 366^7 (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 1875306 relations was collected forming
a 245627 x 246544 matrix.

  The linear algebra stage took 3.4 CPU hours on a
375MHz Celeron using about 45MB of memory, the square
root stage took 14 minutes and found the factorisation
in the first dependency checked.

  On May 14, 2000 it was found that c = p39 * p70

  p39 = 267328709088799112441042271754778643607

  p70 = 1734442813920850476311515484732139025427447677616009563959530585594791

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