Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu|Department of Mathematics, Hope College, Holland, Michigan, USA. tintle@hope.edu