The lower independence number i(G) of a graph G is the minimum size of a maximal independent vertex set in G. The lower indepedence number is equivalent to the independent domination number (i.e., the minimum size of an independent dominating set; cf. Crevals and Östergård 2015, Ilić and Milošević 2017). The (upper) independence number may be similarly defined as the largest size of an independent vertex set in G .

independence number | independence polynomial | independent vertex set