# Pi Mu Epsilon hosts professor Tim Goldberg

### Elon's chapter of Pi Mu Epsilon, the national mathematics honor society, hosted the Lenoir-Rhyne University assistant professor of mathematics for a special guest lecture on April 1.

Goldberg's talk, "Geometry, Algebra, and SET —Oh My!," was given to a crowd that included 36 Elon students and faculty. SET is a fun and addictive mathematical card game, first commercially sold in 1991. Since that time, it has won numerous awards, including a MENSA Select Award in its inaugural year of sales.

The SET deck consists of 81 cards, with each card varying in four features:

shape (either diamond, squiggle, or oval);

number (either one, two, or three);

shading (either solid, striped, or open);

color (either red, green, or purple).

The game begins by dealing out 12 cards. Players then search for a SET, which is a collection of three cards that are related in all four characteristics. But there's a catch: for each characteristic, all three cards must either match or be completely different. For example, the accompanying picture shows 9 SET cards. Each row is a SET, as is each column. Even both diagonals are SETS.

Goldberg's talk focused on the mathematics behind all possible SET combinations. In particular, he unveiled the surprisingly complex geometry and algebraic theory latent in this seemingly simple card game.

As advertised, two lucky Elon students won door prizes: Alec Burke '17 and Taylor Coe '17.

The event concluded with Pi Mu Epsilon's faculty advisor, assistant professor of mathematics Chad Awtrey, advertising the chapter's final speaker of the semester. On Wednesday, May 6, Karin Saoub from Roanoke College will deliver a special guest lecture titled "Snarks on a Train." A snark is a character from a Lewis Carroll poem. Saoub's talk use snarks as a vehicle for discussing applications of an area of mathematics known as Graph Theory.