The fall 2013 meeting was held **November 9, 2013** at **St. Joseph's University**.

**Tom Halverson**(Macalester College)*Permutation, Coagulation, and Fragmentation*- We begin with a random walk on permutations (this "walk" could also be viewed as a very silly way to shuffle cards). This journey will take us through an elegant mathematical story involving permutations, probability, graph theory, and some linear and abstract algebra. Then we will add operations to the mix that "coagulate" and "fragment" points, and we will go on a new random walk in which permutations are replaced by set partitions and we are introduced to the "partition algebra." Beautiful combinatorics will emerge, ending with a surprising connection to alternating sign matrices.

**Michael Pearson**(Executive Director of MAA)*Stirling's Formula: A Monthly Habit*- Stirling's formula provides a remarkably accurate asymptotic estimate for the growth of the factorial n! for large values of n. James Stirling provided a proof in 1730. Perhaps because of he simplicity of the formula and the ease of observing the basic form of the estimate, it's been attracting mathematicians ever since. In fact, it seems that there has been an average of at least three proofs per decade published in the American Mathematical Monthly over the last 70 years, as well as various other notes and articles that build on or expand Stirling's work. We'll take a discursive look at a few of these notes, with a bit of history of some of the contributors. And, in the end, we'll discover a simple way to compute the precise value of the asymptotic constant in Stirling's formula.

**Talitha Washington**(Howard University)*Uncovering Biological Processes Via Mathematical Modeling*- Many biological processes can be better understood via mathematical models. In society, one is concerned about how a disease could spread as well as how to prohibit a disease from becoming an epidemic. In the body, there are mechanisms that are synchronized to maintain a specific level of calcium in the blood. In the cell, a signaling network determines the secretion of luteinizing hormone regulates reproduction. This talk explores these models as well as ways in which mathematics can contribute to biological discoveries.

Student talk schedule (PDF)

Student talk abstracts (PDF)

Section Governor, Annalisa Crannell, Franklin & Marshall College

August 2013

Here's a quick snapshot of MAA by the numbers.

**375,000**

That's the number of students *each year* who take the AMC, a middle- and high-school mathematics competition sponsored by the MAA. This year, the US team scored 3^{rd} at the IMO. Whoop!

**26,000**

That's the number of different pages on the new MAA website (http://www.maa.org/) which was "born" this summer in late July. The MAA has been working hard to make this site more navigable and usable by our members, so you should definitely check it out!

**130**

That's the number of MAA committees. Wow! The MAA is trying hard to make sure no person serves on more than one committee, so we're always looking for fresh faces. If you'd like to join in the fun, check out the list of committees (grouped into sets called "councils") and then feel free to nominate yourself (or have me nominate you, if you're shy). For more information, visit http://www.maa.org/community.

**Station break:** If you've read this far, you're a special person. Who on earth actually *reads* Governor's reports? Well, *you* do, apparently, and so do a handful of other highly conscientious people who care about their professional society. So if you've read this far, the next number is just for you:

**1**

That's the number of people it takes to convince a young mathematician to join the MAA. At this summer's Board of Governor's meeting, person after person said, "The reason I joined the MAA was because [some person I admired] told me I should."

We're at a time of generational shift, and younger people see less value joining (what seems to them like) some club. But it's our youngest colleagues who most need to see the larger world of mathematics - to hear great talks on a wide range of mathematical fields, to learn about different teaching ideas, mathematical software, ideas for balancing teaching and research. I'll even say that getting a young mathematician involved in an MAA committee, at either the section or a national level, is a great way to help both our colleagues and the institutions where they work. By encouraging your colleagues to join and to get involved in the MAA, you, too, can be a person that some young mathematician talks admiringly about years from now.