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{\bf Wen An Liu, Haifeng Li and Bei Li}
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{\bf A Restricted Version of Wythoff's Game}
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E.~Duch\^{e}ne and S.~Gravier present the following open problem: In
Wythoff's game, each player can either remove at most $R$ tokens
from a single heap (i.e. there is an upper bound $R$ on the number
of removing tokens), or remove the same number of tokens from both
heaps but there is no upper bound on the number of removing tokens.
This open problem is investigated and all its P-positions are given.
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