Tag Archives: Latin square

Association schemes for diagonal groups

Sean Eberhard commented on my posts on diagonal groups (see here and here). He is correct; there is an association scheme preserved by the full diagonal group with n factors in the socle; it is non-trivial if n > 2. The details … Continue reading

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Endomorphism monoids of graphs

A monoid is, for me, a set of mappings on a finite domain which is closed under composition and contains the identity mapping. The composition is, of course, associative. Thus, it is “a group without the inverses”. A homomorphism from … Continue reading

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Bluebells, 2

I didn’t give you enough information in the preceding post to find the grid reference to the bluebell wood. Here is some more, which should be more than enough. This is a part of the substitution table (rows and columns … Continue reading

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