nRootedShapes and nUnrootedShapes give the number of (un)rooted binary
trees on n unlabelled leaves.
Source
nRootedShapes corresponds to the Wedderburn-Etherington numbers,
OEIS A001190
nUnrootedShapes is OEIS A000672
nRootedShapes and nUnrootedShapes give the number of (un)rooted binary
trees on n unlabelled leaves.
nRootedShapes corresponds to the Wedderburn-Etherington numbers,
OEIS A001190
nUnrootedShapes is OEIS A000672