All Questions

If $h(T)$ denotes the number of (directed) Hamiltonian paths in the tournament $T,$ what is the range of $h(T)$ as $T$ ranges over all (finite) tournaments $T$? By a classical theorem of Rédei (...

The following is a result of Erdős-Gallai from 1959 (https://link.springer.com/article/10.1007/BF02024498): Given a 2-connected undirected unweighted graph with minimum degree at least $d$, for every ...

Recall that a tournament is a directed graph $T$ such that for every pair of distinct vertices $\{v,w\}$, exactly one of the ordered pairs $(v,w)$, $(w,v)$ is an arc of $T$. A tournament is strongly ...

For $n\ge3$ let $a(n)$ be the minimum number of Hamiltonian paths in a strong (i.e., strongly connected) tournament of order $n.$ Where is $a(n)$ discussed in the literature? Is the exact value ...

Every tournament contains a directed Hamiltonian path (a path visiting every vertex exactly once). Suppose that $T$ is a tournament on $[n]:=\{1,\ldots,n\}$ for some integer $n\geq 2$ with exactly ...

On a paper by Shoham Letzter, available Here, there's a lemma that says as follows: Lemma 0: For every graph $G$, there exist two disjoint sets $U,W\subseteq V(G)$ of equal size, such that there are ...