| dc.contributor.author | Dafik, Mirka Miller, Costas Iliopoulos and Zdenek Ryjacek | |
| dc.date.accessioned | 2014-08-17T01:48:14Z | |
| dc.date.available | 2014-08-17T01:48:14Z | |
| dc.date.issued | 2007-11-05 | |
| dc.identifier.issn | Proceeding | |
| dc.identifier.uri | http://repository.unej.ac.id/handle/123456789/58933 | |
| dc.description | YEAR/VOLUME/NUMBER/PAGE:2007/Novemvember 5-9/39-47 | en_US |
| dc.description.abstract | Since Moore digraphs do not exist for k /= 1 and d /= 1,
the problem of finding the existence of digraph of out-degree d >= 2
and diameter k >= 2 and order close to the Moore bound becomes an
interesting problem. To prove the non-existence of such digraphs, we
first may wish to establish their diregularity. It is easy to show
that any digraph with out-degree at most d >= 2, diameter k >= 2 and
order n = d + d^2 + ... + d^k-1, that is, two less than Moore bound
must have all vertices of out-degree d. However, establishing the
regularity or otherwise of the in-degree of such a digraph is not
easy. In this paper we prove that all digraphs of defect two are
out-regular and almost in-regular. | en_US |
| dc.description.sponsorship | ARC Grant 2004-2007 Australia | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | The University of Newcastle Australia | en_US |
| dc.relation.ispartofseries | The Eighteenth International Workshop on Combinatorial Algorithms;17 | |
| dc.subject | Diregularity, digraph of defect two, degree-diameter problem. | en_US |
| dc.title | On diregularity of digraphs of defect two | en_US |
| dc.type | Article | en_US |
