bug with factorpadic

[John Jones <jj@asu.edu>]

Below is a transcript producing a bug with factorpadic for p=2.

                  GP/PARI CALCULATOR Version 2.1.1 (released)
                i686 running linux (ix86 kernel) 32-bit version
                (readline v4.1 enabled, extended help available)

                       Copyright (C) 2000 The PARI Group

PARI/GP is free software, covered by the GNU General Public License, and 
comes WITHOUT ANY WARRANTY WHATSOEVER.

Type ? for help, \q to quit.
Type ?12 for how to get moral (and possibly technical) support.

   realprecision = 28 significant digits
   seriesprecision = 16 significant terms
   format = g0.28

parisize = 4000000, primelimit = 500000

? allocatemem() to 128.0 MBytes

? f=x^8 + 5792*x^7 + 14671168*x^6 + 21227212800*x^5 + 19188079298432*x^4 + 11096338830817280*x^3 + 4009004198849015808*x^2 + 827336168337500405760*x + 74667146396559795097600;

? factorpadic(f,2,10)

***   bug in GP (Segmentation Fault), please report

------------------

I also get an error message from factorpadic, p=2, for

x^8 + 160*x^7 + 11072*x^6 + 434176*x^5 + 46976*x^4 + 653312*x^3 + 290816*x^2 + 131072*x + 856064

In this case, the error is

  ***   impossible inverse modulo: Mod(256, 512).
 

                                 John Jones


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