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PERFECT 1-FACTORISATIONS OF $K_{16}$

Published online by Cambridge University Press:  07 August 2019

MICHAEL J. GILL
Affiliation:
School of Mathematics, Monash University, Vic 3800, Australia email michael.gill@monash.edu
IAN M. WANLESS*
Affiliation:
School of Mathematics, Monash University, Vic 3800, Australia email ian.wanless@monash.edu

Abstract

We report the results of a computer enumeration that found that there are 3155 perfect 1-factorisations (P1Fs) of the complete graph $K_{16}$. Of these, 89 have a nontrivial automorphism group (correcting an earlier claim of 88 by Meszka and Rosa [‘Perfect 1-factorisations of $K_{16}$ with nontrivial automorphism group’, J. Combin. Math. Combin. Comput. 47 (2003), 97–111]). We also (i) describe a new invariant which distinguishes between the P1Fs of $K_{16}$, (ii) observe that the new P1Fs produce no atomic Latin squares of order 15 and (iii) record P1Fs for a number of large orders that exceed prime powers by one.

Type
Research Article
Copyright
© 2019 Australian Mathematical Publishing Association Inc.

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Footnotes

Research supported by an Australian Government Research Training Program (RTP) Scholarship and by ARC grant DP150100506.

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