Spring 2013 office hours: Monday 3:10--4:10; Wednesday 1:10--3:10; Thursday 2:10--3:10.

   Spring 2013 classes:

• Math 209, Calculus IV, Tuesday and Thursday, 4:20--6:00 in SH 164B.
• Math 210, Intro. to Computer Algebra Systems, Tuesday and Thursday, 11:40--1:20 in SH 356.
• Math 325, Introduction to Mathematical Notation Proofs, Monday and Wednesday 4:20--6:00 in SH 243.
• Math 550, Expander Graphs, Monday and Wednesday, 6:10--7:50 in SH 242.
  

• Joint with Mike Krebs, Expander families and Cayley graphs : a beginner's guide, Oxford University Press, 2011.
  

• Joint with Caleb Emmons and Mike Krebs, K-Quasiderivations, Central European Journal of Mathematics, Volume 10, Number 2, 824--834, 2012.  The original publication is avaliable at www.springer.com.
  
• Joint with Caleb Emmons and Mike Krebs, How to differentiate an integer modulo n, College Mathematics Journal, pgs. 345--353, November, 2009.
• Joint with Mike Krebs, On the spectra of Johnson graphs, Electronic Journal of Linear Algebra, vol. 17, pgs. 154--167, 2008.
  
• A trace formula for finite upper half planes, Journal of the Ramanujan Mathematical Society, 21, no. 4, pgs. 343--363, 2006.
  
• Joint with Audrey Terras, Fourier expansions of complex-valued Eisenstein series on finite upper half planes, International Journal of Mathematics and Mathematical Sciences, vol. 2006.

• Introduction to expander graphs and Ramanujan graphs ( powerpoint or .pdf )