358^49-1

  Henrik Olsen announces the complete factorization of the number
N=(358^49-1)/(358^7-1) from The Expanded Cunningham Table by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = 7 * 7057 * c103

where c103 is a 103 digit composite number given by

 c103 = 3709957731325084931991515682251206023650\
	9914347308186741744832240374012565629144\
	15869671201031712759623

The two polynomials used were

        X^6 + X^5 + X^4 + X^3 + X^2 + X + 1 and
        X - 358^7

with common root 358^7 (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 1866687 relations was collected forming
a 235616 x 235796 matrix.

  The linear algebra stage took 3.3 CPU hours on a
375MHz Celeron using about MB of memory, the square
root stage took 12.3 minutes and found the factorisation
in the first dependency checked.

  On May 9, 2000 it was found that c103 = p37 * p66

  p37 = 6843241601605374619139166270483566009

  p66 = 542134553667483532858959328436512290463827043584226710800359150847

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