 time. However, there are many
algorithms that use heuristics to find colorings that are close to the
minimum.

<P>
The particular algorithm we present here is based on the linear time
<TT>SEQ</TT> subroutine that is used in the estimation of sparse
Jacobian and Hessian matrices&nbsp;[<A
HREF="bibliography.html#curtis74:_jacob">9</A>,<A
HREF="bibliography.html#coleman84:_estim_jacob">7</A>,<A
HREF="bibliography.html#coleman85:_algor">6</A>].  This algorithm
visits all of the vertices in the graph according 