Research project on Dyck Paths
A Dyck path is a lattice path in the nxn square which
does not pass below the diagonal.
Dyck paths are one of
the fundamental objects enumerated by the
Catalan numbers.
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Consider the partial order of Dyck paths where one
path is 'less' than another if it lies below.
What are the properties of this poset? (it is a graded lattice where
the rank function is the area, the generating function is a q-Catalan number, can
we say more?)
Can you calculate its mobius function? What is the relationship
of this order to other
Catalan enumerated objects.
In summer of 2008 I gave this problem to a student, Jennifer Woodcock,
in the M.A. for Teachers program and she produced
the following manuscript.
This page was last edited November 16, 2008.