I'm a mathematician interested in computers. Here are my notes on Hilbert's axioms for plane geometry, and Mizar code which formally proves results on Tarski's geometry axioms, following work of Narboux and Schwabhäuser. My latest published math papers are Poincare duality and periodicity, a joint paper with John Klein, and Combinatorial Proofs of the Lambda Algebra Basis and EHP Sequence. My paper a conjecture of Gray and the p-th power map on Omega^2 S^{2np+1} was just accepted by Proc AMS. Here's my computer resume.
Here's some Gambit Scheme code to calculate the Curtis algorithm in the Lambda algebra.
Here is a 760 line Scheme program lc_v.scm computing essentially the standard reduction function of the Lambda Value Calculus discussed in Felleisen and Flatt's notes on LC_v: http://www.ccs.neu.edu/course/com3357/mono.ps.
My mathematical interests are topology, homotopy theory, high dimensional knots, surgery theory. See my latest preprint Poincaré surgery with John Klein, for recent progress. I've gotten interested in Computer Science, especially Matthias Felleisen's Lambda value calculus, and wrote a paper giving a simpler proof than Barendregt's of the Standard Reduction Theorem in the Lambda Calculus, which explains in what sense the Lambda Calculus is a compiler.
I have recreational Math interests in mathematical physics (even coauthored a paper with a physicist) and PDE (my thesis was essentially on the Maslov characteristic class of Quantum Mechanics).
I generated most of Coxeter's 59 stellations of the icosahedron with Mathematica, including the 3 inline
images above. The starting point is that the icosahedron is given by
3 golden rectangles:
The picture illustrates that the golden mean is ratio of diagonal of a pentagon to a side. Note that the 1st stellation looks quite different from the Mathematica icon. Moreover, the Mathematica/Maple "Stellate" command will not in fact produce stellations. A 5-pointed star is the simplest example of a stellation (of a pentagon).