Tag Archives: Latin squares

BCC29 at Lancaster

Posted on 20/07/2022 by Peter Cameron

Last week we celebrated the 29th British Combinatorial Conference in Lancaster, face to face. (As a side observation, this was by far the largest social gathering I have been at since the start of the pandemic; I found it both … Continue reading →

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The Hall–Paige conjecture

Posted on 18/12/2018 by Peter Cameron

A Latin square of ordern is an n×n array of symbols from an alphabet of size n with the property that each symbol in the alphabet occurs once in each row or column. Two Latin squares L and M are … Continue reading →

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British Mathematical Colloquium, days 3 and 4

Posted on 14/06/2018 by Peter Cameron

The day began with the plenary talk by Paul Seymour, whom I’ve known for longer than almost anyone else at the meeting. He explained that there are many different “ordering” relations on graphs; the two he considers most important are … Continue reading →

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Equitable partitions of Latin square graphs

Posted on 06/02/2018 by Peter Cameron

On our recent trip to Shanghai, Rosemary Bailey and I met Sergey Goryainov, who gave a talk about some joint work with his supervisor Alexander Gavrilyuk at the International Workshop on Bannai–Ito Theory in Hangzhou. I mentioned it in my … Continue reading →

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ACCMCC, Days 4 and 5

Posted on 12/12/2015 by Peter Cameron

Penny Haxell opened proceedings on Thursday with her astonishing work with Ron Aharoni. They give a sufficient condition for a tripartite 3-uniform hypergraph (one whose vertex set is partitioned into three parts so that each hyperedge contains one vertex from … Continue reading →

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From the archive, 9

Posted on 12/05/2015 by Peter Cameron

Looking for a book yesterday, I turned up a file of old papers. One of them I think deserves an afterlife, so I re-typed it and here it is. First, the background. Let A be an n×n matrix. The permanent … Continue reading →

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G. C. Steward lectures 2008

Posted on 05/04/2015 by Peter Cameron

While I was uploading lecture notes, I also put on the page the notes from my G. C. Steward lectures at Gonville and Caius College in 2008. You can find them here. I spent the first half of 2008 in … Continue reading →

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Orbital combinatorics

Posted on 11/02/2015 by Peter Cameron

Yesterday I went to Edinburgh to give a colloquium talk about synchronization, including the recent stuff about butterflies. The day before, I had discussed Artur Schäfer’s work with him, and he expressed a hope that if he went to the … Continue reading →

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A niggling problem

Posted on 24/01/2015 by Peter Cameron

Preparing my talk for the Research Day, I was reminded of a problem I can’t solve, that has niggled me for many years. Maybe someone else can solve it, or maybe I will be encouraged to do it myself. Here … Continue reading →

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Futoshiki squares

Posted on 19/05/2014 by Peter Cameron

Futoshiki is a puzzle in the spirit of sudoku, involving constructing a Latin square from some partial information, which can be found in some newspapers now, including the Saturday Guardian. Probably someone has looked at the mathematics of futoshiki, but … Continue reading →

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