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arXiv · 1804.01859

Sprague-Grundy Function of Symmetric Hypergraphs

Endre Boros·Vladimir Gurvich·Nhan Bao Ho·Kazuhisa Makino·Peter Mursic
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Abstract

We consider a generalization of the classical game of $NIM$ called hypergraph $NIM$. Given a hypergraph $\cH$ on the ground set $V = \{1, \ldots, n\}$ of $n$ piles of stones, two players alternate in choosing a hyperedge $H \in \cH$ and strictly decreasing all piles $i\in H$. The player who makes the last move is the winner. Recently it was shown that for many classes of hypergraphs the Sprague-Grundy function of the corresponding game is given by the formula introduced originally by Jenkyns and Mayberry (1980). In this paper we characterize symmetric hypergraphs for which the Sprague-Grundy function is described by the same formula.

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Endre Boros, Vladimir Gurvich, Nhan Bao Ho, Kazuhisa Makino, Peter Mursic. 2018-04-01. Sprague-Grundy Function of Symmetric Hypergraphs. https://arxiv.org/abs/1804.01859

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