The clique operator on cographs and serial graphs Celia Picinin de Mello Sexta-feira, 16 de agosto sala: 96 horario: 18:00hs Abstract: The {\bf clique graph} of a graph $G$ is the intersection graph $K(G)$ of the (maximal) cliques of $G$. The iterated clique graphs $K^{n}(G)$ are defined by $K^{0}(G)=G$ and $K^{i}(G)=K(K^{i-1}(G))$, $i>0$ and $K$ is the clique operator. A {\bf cograph} is a graph with no induced subgraph isomorphic to $P_{4}$. In this article we describe the $K$-behaviour of cographs and give some partial results for the larger class of serial (i.e. complement-disconnected) graphs. Este trabalho e em coautoria com: F. Larri\'{o}n, A. Morgana, V. Neumann-Lara e M. A. Piza\~{n}a