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Tag Archives: species
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
Posted in books, history
Tagged cycle index, growth rates, Hilbert series, LMS Durham symposium, species
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Eigenspecies
The title of this post is halfserious: it is designed to catch attention, but I think there are interesting things lurking here which deserve more exploration. Species A species describes a class of objects built on finite sets, in a … Continue reading
Posted in exposition
Tagged binary trees, cographs, gorilla, Nfree graphs, oligomorphic permutation groups, species
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Combinatorial physics
This is to announce a new academic discipline, combinatorial physics. This week I have been at a workshop on the subject (more on this later), and there are several conferences scheduled (one in France, one just approved at the Galileo … Continue reading
LTCC course finished
Yesterday was the last day of my LTCC course on Enumerative Combinatorics. Thanks to the students who stuck it out to the end. I produced notes week by week and now you can find the complete notes on this site. … Continue reading