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{\bf Benjamin Wieland}
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{\bf Large Dihedral Symmetry of the Set of Alternating Sign Matrices}
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We prove a conjecture of Cohn and Propp, which refines a conjecture of
Bosley and Fidkowski about the symmetry of the set of alternating sign
matrices (ASMs).  We examine data arising from the representation of
an ASM as a collection of paths connecting $2n$ vertices and show it
to be invariant under the dihedral group $D_{2n}$ rearranging those
vertices, which is much bigger than the group of symmetries of the
square.  We also generalize conjectures of Propp and Wilson relating
some of this data for different values of $n$.

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