Dih(8) is the dihedral group of order 8, i.e. the symmetries of the octagon, with the actions of flipping and rotating 45 degrees.
Cool I just looked it up in a textbook and it has 16 elements. So it cannot be isomorphic to either of the above two groups because there is not a bijection(1-1 onto function) between the groups.
Cool I just looked it up in a textbook and it has 16 elements.
It is conflicting notation. Some books use $\displaystyle D_{2n}$ for the dihedral group because the dihedral group on $\displaystyle n$ verticies is of order $\displaystyle 2n$.