  Transport through an Anderson junction (two macroscopic electrodes coupled to
an Anderson impurity) is dominated by a Kondo peak in the spectral function at
zero temperature. The exact single-particle Kohn-Sham potential of density
functional theory reproduces the linear transport exactly, despite the lack of
a Kondo peak in its spectral function. Using Bethe ansatz techniques, we
calculate this potential exactly for all coupling strengths, including the
cross-over from mean-field behavior to charge quantization caused by the
derivative discontinuity. A simple and accurate interpolation formula is also
given.
