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{\bf Joanne L. Hall}
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{\bf Graphs Associated with Codes of Covering Radius 1 and Minimum Distance 2}
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The search for codes of covering radius $1$ led \"{O}sterg{\aa}rd,
Quistorff and Wassermann to the OQW method of associating a unique
graph to each code.  We present results on the structure and existence
of OQW-associated graphs.  These are used to find an upper bound on
the size of a ball of radius $1$ around a code of length $3$ and
minimum distance $2$.  OQW-associated graphs and non-extendable
partial Latin squares are used to catalogue codes of length $3$ over
$4$ symbols with covering radius $1$ and minimum distance $2$.

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