For fixed a and d the following diagrams show all possible
regularity + codim against degree
degree - regularity against codim
degree - codim against regularity
codim against regularity for semigroups with regularity - degree + codim = 0
regularity on top of codim against degree.
The line corresponds to the Eisenbud-Goto bound.
d = 3:
a = 3:
a = 4:
a = 5:
d = 4:
a = 2:
a = 3:
d = 5:
a = 2: