Paper 3:  Some ternary Diophantine equations of signature (n, n, 2)
          by Nils Bruin

The code for this paper takes around 200 seconds to run on a
64-bit 2.4GHz AMD processor.

Changes since book release:

V2.12:  The intrinsics SwapExtension and OrderedGenerators are now
        part of the Magma distribution, so are no longer provided
        separately.