On tournaments having a unique Hamiltonian circuit
Michael R. Shelor · 1977
A tournament is a directed complete graph. A Hamiltonian circuit is a circuit which passes through each vertex of the graph once and only once. This note examines the family T of all nonisomorphic tournaments on n vertices which n have a unique Hamiltonian circuit. We let T = IT I. In [1] Douglas gives a n n graphical characterization of the family T, n and from this characterization obtains an involved formula for calculating the values T. In particular n n =