Today is the birthday of two famous physicists, though that is not how they are commonly remembered. More »

On May 22, 2010, Martin Gardner died, unexpectedly, at age 95. The previous sentence contains a paradox* explained within his book *The Unexpected Hanging and Other Mathematical Diversions*, one of 15 books known collectively as “the Canon,” comprising hundreds of the Mathematical Games columns Martin wrote for *Scientific American* between 1956 to 1981.

My fifth-grade science class had old copies of *Scientific American* available, and I read a few of those columns. From him I learned that math can be fascinating, perhaps one of the great lessons I’ve learned in life. I found out that the library had more issues, and whole books by Martin. I tracked down more of his columns on microfiche.

After reading all those columns, school-level math was easy. Years later, I tried to follow in Martin’s footsteps by putting recreational mathematics online. For example, I contributed a diagram of pentagon tiling to a very early version of *MathWorld*. “Tiling with Convex Polygons” was one of Martin’s columns, in his book *Time Travel and Other Mathematical Bewilderments*; today, you can explore these objects in Wolfram|Alpha.

Martin’s works influenced generations of mathematicians, and many of the topics he discussed can be found here at Wolfram|Alpha. For a Lewis Carroll expert like Martin, a snark was “something hard to find”, as in Carroll’s “The Hunting of the Snark” (for which Martin compiled a companion volume, *The Annotated Snark*). So he used the word “snark” to describe a graph with three edges attached to each node, but which could not be 3-colored without any clashes at a node. More »