Tag Archives: cycle index

Oligomorphic Permutation Groups

Posted on 17/04/2017 by

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

Posted on 16/04/2016 by

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

Posted on 12/06/2014 by

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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