Nonattacking Queens on a Triangle

Following the excellent suggestion of an anonymous referee, for which the author is grateful, we put the discussion in a wider context by generalizing the means defined by (1). We state a set of axioms, which, if satisfied by a class of functions, will entitle those functions to be called means. The axioms will be chosen by abstracting the most important properties of f (t) in (1). We say that a function F (a, b) defines a mean for a, b > 0 when