On Mon, Nov 17, Abdullah will talk about so-called median orders of tournaments. These things were used by Havet & Thomasse to give a (new) proof of Seymour's 2nd neighborhood conjecture for tournaments. (A tournament, btw, is a directed graph in which, for every two vertices u,v, exactly one of the two directed edges (u,v) or (v,u) is present.) |

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