Liz and I were on sabbatical last year (2006-07), spending time in Montana and in England. In the fall of 2007, I taught Calculus 3 and Combinatorics. In the spring of '08, I'll be teaching Patterns and Order and our new Transitions course.

I'm from Miami and I'm a lifelong Dolphins fan. Wait till next year. I got my BA from the University of Florida in 1977 and my Ph.D. from the University of North Carolina in 1983.  My mathematical interests include combinatorics, geometry and algebra.  I love watching baseball and playing softball.  I'm into rock climbing these days, and so are my wife and mathematical teammate, Liz McMahon, and my two daughters, Rebecca and Hannah.  Here are a few family pictures that don't stink too much.

I'm involved in the following math competitions: 

• LVAIC Mathematics Competition
• Weekly Barge Competition
• Putnam Exam
• Math Bowl

I've worked on matroids (representability questions), greedoids (extending the Tutte polynomial from graphs and matroids to greedoids), graph invariants & reliabilty, and geometric questions related to matroids (comparing matroid automorphism groups to Coxeter groups). I'm also Lafayette's REU contact, so contact me if you're interested or have questions.  Here is a list of published and current work. As a sample of what my writing has degenerated into, here's an April Fool's article published by Math Horizons in 2007.

By the way, if you're interested in the card game SET, Liz and I have a variation we call the End Game (with apologies to chess aficionados). You can read about it in English, Spanish, French or German here (Click on "Other ways to play SET"). Our other SET connection: Our daughter Hannah won the first national SET competition; she is the First SET Grand Master.

I've taught a variety of math courses and one non-math course. The math courses include Calculus, Numerical Analysis, Linear Algebra, Abstract Algebra, Real Analysis, Combinatorics, Graph Theory, Symmetry & Geometry, Discrete Structures, Operations Research and Statistics.  The non-math course was a VaST course on Intelligence Testing and other controversies in science. For some geometric fun, check out Euler line & nine point circle and Euler line & center of nine-point circle constructions in Cinderella. You can also play with the Toricelli point of a triangle. I've directed several senior theses in combinatorics, geometry and game theory (Lis Edwards did one on geometry) and independent studies on a variety of topics (three of which were with Katya Jager, Prince Chidyagwai and Rob McEwen). 

I'm a co-advisor (with Liz McMahon and Ethan Berkove) for Lafayette's very active Hillel Society. History professor Bob Weiner is the Hillel advisor and Jewish Chaplain at Lafayette. We have Shabbat dinners every Friday night - stop by at 6:00.  

Some treats at the Math Picnic