Dear John, You make a slight mistake, the unit group of Z[sqrt(2)] has rank 1, so although you have unique factorization up to units this might still give you a lot of different a and b satisfying the criteria.
See for example: sage: [a^2-2*b^2 for (a,b) in [(3, 1), (5, 3), (13, 9), (27, 19), (75, 53)]] [7, 7, 7, 7, 7] -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
