The Experts below are selected from a list of 9 Experts worldwide ranked by ideXlab platform

Bodo Lass - One of the best experts on this subject based on the ideXlab platform.

  • the Algebra of Set functions ii an enumerative analogue of hall s theorem for bipartite graphs
    The Journal of Combinatorics, 2012
    Co-Authors: Bodo Lass
    Abstract:

    Triesch (1997) [25] conjectured that Hall's classical theorem on matchings in bipartite graphs is a special case of a phenomenon of monotonicity for the number of matchings in such graphs. We prove this conjecture for all graphs with sufficiently many edges by deriving an explicit monotonic formula counting matchings in bipartite graphs. This formula follows from a general duality theory which we develop for counting matchings. Moreover, we make use of generating functions for Set functions as introduced by Lass [20], and we show how they are useful for counting matchings in bipartite graphs in many different ways.

  • The Algebra of Set functions I: The product theorem and duality
    European Journal of Combinatorics, 2012
    Co-Authors: Bodo Lass
    Abstract:

    We give a comprehensive introduction to the Algebra of Set functions and its generating functions. This Algebraic tool allows us to formulate and prove a product theorem for the enumeration of functions of many different kinds, in particular injective functions, surjective functions, matchings and colourings of the vertices of a hypergraph. Moreover, we develop a general duality theory for counting functions.

Ifeoma Nnochiri - One of the best experts on this subject based on the ideXlab platform.

C. Emmanuel Eziokwu - One of the best experts on this subject based on the ideXlab platform.