with partition types [S] = [U] = (f;
g; f; g) and [T] = (f; g; f;
g). Since
[B1] = (f; g; f;
g), neither S nor U is R C-equivalent to B1. This means that
the corresponding symmetries, rotation by 90 and 270, are not in R C.
What about T? As suggested above, T can be obtained from B1 by reversing the
orders of both the rows and the columns: