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About

38^91+1

  Henrik Olsen announces the complete factorization of the number
N=(38^91+1)/(38^13+1) from Richard Brent's Factor Tables by the
Special Number Field Sieve (SNFS).  It was previously known that

        N = 29 * 239 * 16927 * 423277 * c110

where c110 is a 110 digit composite number given by

        c110 = 3366045425774464752096938170116372928101\
               4666384288385765793775176370241552595261\
               634243878448115651711974924153

The two polynomials used were

        X^6 - X^5 + X^4 - X^3 + X^2 - X + 1 and
        X - 38^13

with common root 38^13 (mod N).

The linear algebra phase was done by Conrad Curry.

On 26 Nov, 1999 it was found that c110 = p47 * p64 where

        p47 = 10266536220316255483758618648521254491255005689

        p64 = 3278657332463758079471550699426387852039147791504329628016494977

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Last Update: Sat, 28 Feb 2004