  We consider the problem of solving linear systems of equations arising with
limited-memory members of the restricted Broyden class of updates and the
symmetric rank-one (SR1) update. In this paper, we propose a new approach based
on a practical implementation of the compact representation for the inverse of
these limited-memory matrices. Numerical results suggest that the proposed
method compares favorably in speed and accuracy to other algorithms and is
competitive with several update-specific methods available to only a few
members of the Broyden class of updates. Using the proposed approach has an
additional benefit: The condition number of the system matrix can be computed
efficiently.
