GRAPH THEORY SEMINAR (SPRING 2009)
GRAPH THEORY SEMINAR
SCHEDULE (SPRING 2010)
Tuesday 3:00-3:50 pm, Alavi
- January 12
- January 19
From a Checkerboard Problem to an Edge Coloring Problem
- January 26
Toward Graph Labelings
- February 2
How to Draw a Tait-Colored Graph
- February 16
Application of Cores to Graph Coloring Problems
Abstract: The k-core of a graph is the maximal subgraph
with minimum degree at least k. Cores have a very natural
application to graph coloring. They can be used to prove the core
number bound, an upper bound for chromatic number which is both
sharp and easy to compute. Cores make possible simpler proofs of
existing results including Brooks' Theorem and suggest extensions of some results.
Time permitting, we will discuss the Nordhaus-Gaddum Theorem and using
cores to determine which graphs achieve this upper bound.
- February 23
How many fours are needed?
A well known problem challenges us to write an expression using four 4s to obtain each integer from 1 to 100.
1 = 44/44
2 = 4x4/(4+4)
3 = sqrt(4x4)-4/4
But do we really need as many as four 4s?
We are allowed to use common mathematical operations that
are represented with symbols, but not words or
letters, +, ?, x, /, sqrt (but using the surd symbol),
factorial, decimal point, etc. We must not use any other digits or letters.
What is the fewest number of 4s needed to represent every natural number?
I'll bet it is less than four.
- March 16
Vertex Rainbow Colorings of Graphs
- March 23
Sigma Colorings of Graphs
- March 30
Local Metric Sets in Graphs
- April 6
Modular Edge-Graceful Graphs
Cents and Sensitivity
- April 13
- April 13
Weston Mitchell :
Detour Distance in Graphs
Previous Graph Theory Seminars