Minimal and Maximal \(e=1\) Functions

An \(e=1\) function is a function \(f: V(G) \rightarrow [0,1]\) such that every non-isolated vertex \(u\) is adjacent to some vertex \(v\) such that \(f(u) + f(v) = 1\), and every isolated vertex \(w\) has \(f(w) = 1\). A theory of \(e=1\) functions is developed focussing on minimal and maximal \(e=1\) functions. Relationships are traced between \(e=1\) parameters and some well-known domination parameters, which lead to results about classical and fractional domination parameters.