Bruhat graph of the symmetric group and size of special intervals
11/10/2007 Quinta-feira, 11 de Outubro de 2007, 10h00, Anfiteatro
Alessandro Conflitti
(CMUC, Portugal)
We consider a chain inside the directed Bruhat graph of the symmetric group made up of involutions with special algebraic properties (i.e. maximal elements of the corresponding parabolic subgroup) and we enumerate both the cardinality of the interval between any couple of them and the number of vertices unconnected with any of them.
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