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arXiv · 1807.11109

Waiter-Client Maximum Degree Game

Michael Krivelevich·Nadav Trumer
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Abstract

For integers $n, D, q$ we define a two player perfect information game with no chance moves called the Waiter-Client Maximum Degree game. In this game, two players (Waiter and Client) play on the edges of $K_n$ as follows: in each round, Waiter offers $q+1$ edges which have not been previously offered. Client then claims one of these edges, and Waiter claims the rest. When less than $q+1$ edges which have not been offered remain, Waiter claims them all and the game ends. After the game ends, Client wins if in the graph of his edges, there is no vertex with degree at least $D$, and Waiter wins otherwise. For various values of $q = q(n)$, we study the maximum degree of Client's graph obtained by perfect play. We determine the asymptotic value of Client's maximum degree for the cases $q = o\left( \frac{n}{\ln n} \right)$ and $q = \omega\left( \frac{n}{\ln n} \right)$. For the unbiased case $q=1$, we prove that when both players play perfectly the maximum degree $D$ Client achieves satisfies: $D = \frac{n}{2} + \Theta(\sqrt{n \ln n})$.

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Michael Krivelevich, Nadav Trumer. 2018-07-29. Waiter-Client Maximum Degree Game. https://arxiv.org/abs/1807.11109

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