Energy of strongly connected digraphs whose underlying graph is a cycle

The energy of a digraph is defined as E (D) = Pnk= where z1,...,zn are the eigenvalues of the adjacency matrix of D. This is a generalization of the concept of energy introduced by I. Gutman in 1978. When the characteristic polynomial of a digraph D is of the form (0.1) φD (z) = where b0 (D)=1 and b...