Tag Archives: cycle index

Oligomorphic Permutation Groups

In 1988, there was an LMS Durham symposium on model theory and groups. I had been developing the theory of oligomorphic permutation groups for some time: these are the permutation groups G on Ω with the property that the number … Continue reading

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Advanced Combinatorics: the St Andrews lectures

Three years ago, when I joined the School of Mathematics and Statistics at the University of St Andrews, it was suggested that I might like to give a final year MMath module on “Advanced Combinatorics”. No compulsion. Well, of course … Continue reading

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Categorification, step 1

Today at the St Petersburg meeting, Igor Frenkel talked about categorification. He explained that there are five levels (maybe more!) and one has to take certain steps between them; he illustrated with an example, where level 0 was Jacobi’s Triple … Continue reading

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