Independence complexes and edge covering complexes via Alexander duality.
Let be an integer-valued function defined on the vertex set of a graph . A subset of is an -dominating set if each vertex outside is adjacent to at least vertices in . The minimum number of vertices in an -dominating set is defined to be the -domination number, denoted by . In a similar way one can define the connected and total -domination numbers and . If for all vertices , then these are the ordinary domination number, connected domination number and total domination...
Let be a graph with order , size and component number . For each between and , let be the family of spanning -edge subgraphs of with exactly components. For an integer-valued graphical invariant , if is an adjacent edge transformation (AET) implies , then is said to be continuous with respect to AET. Similarly define the continuity of with respect to simple edge transformation (SET). Let and be the invariants defined by , . It is proved that both and interpolate...