3 papers
math.CO2023
Reciprocals of thinned exponential series
David Galvin, John Engbers, Clifford Smyth
The reciprocal of has a power series about in which all coefficients are non-negative. Gessel [Reciprocals of exponential polynomials and permutation enumeration, Aust…
math.CO2014
Reversible peg solitaire on graphs
John Engbers, Christopher Stocker
The game of peg solitaire on graphs was introduced by Beeler and Hoilman in 2011. In this game, pegs are initially placed on all but one vertex of a graph . If forms a pat…
math.CO2012
Counting independent sets of a fixed size in graphs with a given minimum degree
John Engbers, David Galvin
Galvin showed that for all fixed and sufficiently large , the -vertex graph with minimum degree that admits the most independent sets is the complete bipartite graph…