### GEORGE MASON
UNIVERSITY

DEPARTMENT OF MATHEMATICAL
SCIENCES

COLLOQUIUM

FEBRUARY 13, 2015

**Speaker: **
Michael Somos, Georgetown University

**Title: ***
Elliptic sequences and Pfaffian Triples
*

**Abstract:**
Elliptic sequences -- a generalization of elliptic
divisibility sequences -- can be defined by an
infinite number of three term homogeneous fourth
degree algebraic equations each of which is
determined by a triple of quadruples of positive
integers which I have named Pfaffian triples.
I have recently discovered some combinatorial
properties of Pfaffian triples which relate them
to sequences in the On-Line Encyclopedia of Integer
sequences (OEIS). A brief introduction to Elliptic
sequence and Pfaffian triples is found in my Essay
"In the Elliptic Realm" which is on the web.

**Time:** Friday, February 13, 2015, 3:30-4:20 p.m.

**Place:** Exploratory Hall, room 4106

**Refreshments** will be served at 3:00 p.m.

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