Tag Archives: derangements

Perth, week 4

And now the time in Adelaide and Perth is over. We are back in London, having arrived on the same day as we left Australia. This was the first time I have done this, and I really don’t recommend it. … Continue reading

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Perth, week 1

The first week of the visit is over. The weather has been quite cold, but it is likely to improve as time goes on. The best day so far was yesterday, when we went to Yanchep National Park and had … Continue reading

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Green on derangements

I have to mention Ben Green again. Yesterday he gave a lovely colloquium talk on a problem I had cracked my head against some years ago without much success. As usual with derangements, the story begins with a classical result: … Continue reading

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Asymptotic group theory, 2

Inna Capdeboscq started proceedings this morning with a talk about one small part of the second-generation (Gorenstein–Lyons–Solomon) proof of the Classification of Finite Simple Groups. What she described will be volume 8 of the complete proof, if I remember correctly. … Continue reading

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Finding derangements without CFSG

Nearly two years ago, I posed the problem of finding an “elementary” deterministic polynomial-time algorithm for finding a fixed-point-free element (or derangement) in a transitive permutation group. The background is that there are so many fpf elements (at least a … Continue reading

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Pretty structures

I was at the Pretty Structures conference in Paris last week. The original conference in what became this sequence was called Pretty Things. Perhaps this is not serious enough for a meeting held at the Institut Henri Poincaré, I don’t … Continue reading

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