Fusion Rings Arising from Normal Hopf Subalgebras
For any normal commutative Hopf subalgebra K = kG of a semisimple Hopf algebra we describe the ring inside kG obtained by the restriction of H-modules. If G = $G={\mathbb{Z}}$p this ring determines a fusion ring and we give a complete description for it. The case $G={\mathbb{Z}}_{p^n}$ and some other applications are presented.