New and Explicit Constructions of Unbalanced Ramanujan Bipartite Graphs [article]

Shantanu Prasad Burnwal, Kaneenika Sinha, Mathukumalli Vidyasagar
2020 arXiv   pre-print
The objectives of this article are three-fold. Firstly, we present for the first time explicit constructions of an infinite family of unbalanced Ramanujan bigraphs. Secondly, we revisit some of the known methods for constructing Ramanujan graphs and discuss the computational work required in actually implementing the various construction methods. The third goal of this article is to address the following question: can we construct a bipartite Ramanujan graph with specified degrees, but with the
more » ... restriction that the edge set of this graph must be distinct from a given set of "prohibited" edges? We provide an affirmative answer in many cases, as long as the set of prohibited edges is not too large.
arXiv:1910.03937v2 fatcat:dfxkenurzjbl7czlky7vewxkt4