454-457In families of benzenoid isomers, the molecules with maximum (minimum) Kekulé structure counts should possess maximum (minimum) stability and other distinguished properties. Identifying these extremal isomers turns out to be a difficult task. In this paper we solve such a problem for the class of isomers B(m,n), obtained from a benzenoid molecule B by attaching to its two fixed sites linear polyacene fragments of length m and n; m + n = constant
