Algebra and Combinatorics Seminar: Rafael S. González D’León, Loyola University Chicago, On Whitney numbers of the first and second kind, or is it the other way around?
SAS 4201The Whitney numbers of the first and second kind are a pair of poset invariants that are relevant in various areas of mathematics. One of the most interesting appearances of these numbers is as the coefficients of the chromatic polynomial of a graph. They also appear as counting regions in the complement of a real…