in this paper we find systems of subgroups of a finite‎ ‎group‎, ‎which $bbb p$nobreakdash-hspace{0pt}subnormality guarantees supersolvability‎ ‎of the whole group‎.

Schelling's model is an influential that reveals how individual perceptions and incentives can lead to residential segregation. Inspired by a recent stream of work, we study welfare guarantees complexity in this with respect several measures. First, show while maximizing the social NP-hard, computing assignment agents nodes any topology graph approximately half maximum be done polynomial time. ...