Hypergraph vertex degree
= Hypergraph vertex degree
{title2=$d_H(u)$}
The degree of a vertex $u$ in a <hypergraph> is the number of hyperedges containing $u$. For a <uniform hypergraph>, summing degrees counts each hyperedge once for each of its vertices, so $\sum_u d_H(u)=r e(H)$. In a <multihypergraph>, incidences are counted with multiplicity.