Bipartite multigraphs with expander-like properties
2007 (English)In: Discrete Applied Mathematics, ISSN 0166-218X, Vol. 155, no 13, 1667-1677 p.Article in journal (Refereed) Published
This note considers the following combinatorial question: "For which integers d and functions f(d) does there exist, for every large enough v, a bipartite d-regular multigraph on 2v nodes with node sets V and W having the following property: For every U that is a subset of either V or W, the cardinality of the set of neighbours of U is at least f(d)(vertical bar U vertical bar)?" Graphs with the above property seem to behave well also with respect to other, more complicated, expander-like properties. We provide results for d in (5,6,7,81 and give a description of a fairly general methodology for devising computer-assisted proofs for a wide class of mathematical claims using interval arithmetic.
Place, publisher, year, edition, pages
2007. Vol. 155, no 13, 1667-1677 p.
expander graphs, probabilistic method, interval arithmetic
IdentifiersURN: urn:nbn:se:kth:diva-37006DOI: 10.1016/j.dam.2007.03.001ISI: 000249236300002ScopusID: 2-s2.0-34547480916OAI: oai:DiVA.org:kth-37006DiVA: diva2:431814