Author Archives: Peter Cameron

About Peter Cameron

I count all the things that need to be counted.

An apology

What would life be like if I could remember all the things I ever knew? Yesterday I was led to something I posted here twelve years ago. This was based on a talk to the London Algebra Colloquium by Mark … Continue reading

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A week in Florida

The week before last I was at the Deerfield Beach Resort in Florida, about halfway between Miami and Donald Trump’s place. My children could not believe it when I told them (I am not very good at holidays). Of course … Continue reading

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Cambridge

This is in a sense a follow-up to my earlier post here, describing how the 6-month programme at the Isaac Newton Institute had come to a premature end because of the covid pandemic. The time I spent in Cambridge then … Continue reading

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The enhanced power graph is weakly perfect

Earlier this year, I posed a combinatorial problem, a solution to which would imply that, for any finite group G, the enhanced power graph of G is weakly perfect, that is, has clique number equal to chromatic number. Recall that … Continue reading

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More on the 3p paper

I wrote here about Peter Neumann’s paper on primitive permutation groups of degree 3p, where p is a prime number. Well, summer is almost over, but my undergraduate research intern Marina Anagnostopoulou-Merkouri and I have done our work and produced … Continue reading

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Student meetings

Lots of things have happened and not been noted, sorry. I will try to catch up a bit over the next few weeks. In the past few weeks I have spoken at two student-organised conferences. First, in July, was the … Continue reading

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BCC29 at Lancaster

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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Why I’d like to see this solved

I am aware that quite a number of people have been captivated by the problem I posed. So here is the motivation for it, with some additional remarks and commennts. First, to repeat the problem: Problem: Let n be a … Continue reading

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A request

In 1956, Helmut Wielandt proved that a primitive permutation group whose degree is twice a prime p is doubly transitive, unless p has the form 2a2+2a+1, in which case the group has rank 3, and its subdegrees are a(2a+1) and … Continue reading

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I’d like to see this solved

Here is a problem that I would really like to see solved. I have spent quite a bit of time on it myself, and have suggested it to a few other people, but it still resists all attacks, though it … Continue reading

Posted in doing mathematics, open problems | 9 Comments