DEPARTMENT OF MATHEMATICAL SCIENCES

APPLIED AND COMPUTATIONAL MATHEMATICS SEMINAR

**Speaker:** Tyrus Berry, Mathematical Sciences, George Mason University

**Title: ***
Convergence of periodically-forced rank-type equations
*

**Abstract:**
Consider a difference equation which at each step takes on the k-th
largest output of m functions of the previous m terms of the sequence.
If the functions are also allowed to change periodically as the
difference equation evolves this is analogous to a differential
equation with periodic forcing. A large class of such non-autonomous
difference equations are shown to converge to a periodic limit which
is independent of the initial condition. The period of the limit does
not depend on how far back each term is allowed to look back in the
sequence, and is in fact equal to the period of the forcing.

**Time:** Friday, Sep. 17, 2010, 1:30-2:30 p.m.

**Place:** Science and Tech I, Room 242

Department of Mathematical Sciences

George Mason University

4400 University Drive, MS 3F2

Fairfax, VA 22030-4444

http://math.gmu.edu/

Tel. 703-993-1460, Fax. 703-993-1491