## Abstract A graph has the neighbor‐closed‐co‐neighbor, or ncc property, if for each of its vertices __x__, the subgraph induced by the neighbor set of __x__ is isomorphic to the subgraph induced by the closed non‐neighbor set of __x__. As proved by Bonato and Nowakowski [5], graphs with the ncc p
Partitioning a graph into two isomorphic pieces
✍ Scribed by Anthony Bonato; Richard Nowakowski
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 137 KB
- Volume
- 44
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A simple graph G has the neighbour‐closed‐co‐neighbour property, or ncc property, if for all vertices x of G, the subgraph induced by the set of neighbours of x is isomorphic to the subgraph induced by the set of non‐neighbours of x. We present characterizations of graphs with the ncc property via the existence of certain perfect matchings, and thereby prove that the ncc graphs can be recognized in polynomial time. Operations preserving the ncc property are discussed, and the graphs with the ncc property that are r‐regular, where r ≤ 5, are classified. The graphs with the ncc property that are locally H, for certain graphs H are classified. Infinite graphs with the ncc property are discussed. © 2003 Wiley Periodicals, Inc. J Graph Theory 44: 1–14, 2003
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