3.[Wor] Consider the tree SYT of (unshifted) standard Young
tableaux, with
the tree structure generated by containment. For any node with a
symmetric shape, there is an automorphism of SYT (as an unlabeled
tree) that transposes all
nodes in the subtree rooted at the node and leaves all other nodes fixed.
Computation suggests
that all automorphisms of SYT are compositions of these transpose
automorphisms (with the identity being the composition of zero
transpose automorphisms).
Computation further suggests that each node of SYT is
determined up to transpose by the census (cardinalities) of the ranks of the
subtree rooted at the node.