Tag Archives: road closure conjecture

Research trips in February

I don’t know how things have got so busy. I had two interesting trips in February; I worked hard, and some interesting mathematics resulted; but I don’t seem to have found the time to describe it. So here goes. This … Continue reading

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The Wall conjecture extended

Tim Wall boldly conjectured in 1961 that the number of maximal subgroups of a finite group G is at most |G|−1. (This would be best possible, since the the elementary abelian 2-group attains this bound.) He proved that the conjecture … Continue reading

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Road closures and idempotent-generated semigroups

The University of St Andrews is installing a biomass boiler, to provide hot water to heat University buildings, on the old paper mill site at Guardbridge. The water has to be piped four miles to St Andrews, and this big … Continue reading

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