### Fall 2009 Office Hours

- MWF 10-11 am, TWTh 2:30-3:30 pm, TTh 11--12 am, and by appointment.

###
My Mathematical Interests

I am interested in analytic number theory. Some of my recent papers involve sieve
methods, Sidon sequences, distribution of values of the Euler-phi function, and
divisors of factorials. Some of my recent papers are
available for download in pdf and dvi formats.
I have Erdös
number 1, but so do over 500 other people. My one paper
with Erdös is on divisors of factorials.

###
Recreational Mathematics

- What day of the week was July 4, 1776? If you want to learn how to answer
questions like this, check out the
**Doomsday
Rule.**

- Start with 14 pegs in the following configuration:

Start jumping pegs as you do in checkers; remove the jumped pegs as you go.
Can you end up with just one peg? If you want to learn how to do problems like
this, check out **Peg Solitaire**.

### Separated at Birth?

I spent three years working at the National Science Foundation in Arlington,
Virginia. People would occasionally mistake me for Representative Peter DeFazio,
D-Oregon. Compare for yourself.

### Pictures from France

In July 2004, Mary and I went on barge cruise in Burgundy. Here are
some pictures from the trip.