# Algebra, Geometry and Cryptology Seminar

Fall 2017
Fridays, 3:00-3:50
Location: MB124

The Algebra, Geometry and Cryptology (AGC) Seminar meets on selected Fridays, dates indicated below. Everybody interested is welcome to attend and participate (enrollment is not required). The seminar is co-organized by Zach Teitler and Marion Scheepers. If you wish to present in the seminar or need information, please contact Zach Teitler at zteitler@boisestate.edu.

### August 25:

Open problems & Planning

Topology Seminar

### September 8:

Scott Andrews, Boise State University
The $q,t$-Catalan numbers
The Catalan numbers $C_n$ enumerate many different combinatorial objects, including triangulations of an $(n+2)$-gon, 123-avoiding permutations, and Dyck paths. There are two $q$-analogues of the Catalan numbers, both of which turn out to be specializations of the more general $q,t$-Catalan numbers. In this talk I will introduce the Catalan numbers and the idea of a $q$-analogue of a number and I will define the $q,t$-Catalan numbers.

Topology Seminar

TBA

TBA

TBA

### October 13:

Aaron Bertram, University of Utah
The Tropical Nullstellensatz
The (weak) Hilbert Nullstellensatz states that if a system of polynomial equations in several variables has no complex solutions then the equation $1 = 0$ must be a combination of the polynomial equations in the system. In this talk, I will discuss a version of this theorem that holds when complex numbers are replaced with tropical numbers. This is joint work with Rob Easton.

Topology Seminar

TBA

TBA

TBA

TBA

### November 24:

No seminar meeting (Thanksgiving holiday)

TBA

TBA