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Wythoff's game is a variation of the classical Nim - There are two heaps and the players take turns either taking any amount from one heap, or the same amount of both heaps. The winner is the one making the last move.

Lasker's Nim is the classical Nim with the additional rule that instead of reducing one of the heaps, you can split one into two heaps.

Lasker's Nim can be solved by using the Sprague-Grundy theorem, but the solution for Wythoff's game is descerned differently by looking for "cold positions" that allow for a win and follow a certain pattern.

Now, I have come across a combination of these two games: A Nim variation where you can either take any amount from one heap, or take the same amount from two heaps, or split an existing heap into two new heaps. And I am a bit lost on how to find the winning strategy. Does anyone know if this particular variation has its own name? I have found a few variations that combine Nim and Wyrthoff's game, going by the name of "Nimhoff", but none of these seem to include the rule that you can split a heap into two.

https://www.sciencedirect.com/science/article/pii/009731659190070W http://www.wisdom.weizmann.ac.il/~fraenkel/Papers/WytBridgeAmendedOct25.pdf http://www.wisdom.weizmann.ac.il/~fraenkel/Papers/WythoffWisdomJune62016.pdf

Is there someone who has ideas, or maybe even a solution for that particular Nim-Variation? I am uncertain how to proceed from here.

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  • $\begingroup$ This question was also posted (by an independent account) on MSE at math.stackexchange.com/questions/3092336/… $\endgroup$
    – Mark S.
    Jan 30, 2019 at 18:54
  • $\begingroup$ I'm voting to close this question as off-topic because there is an active version at Math.SE. $\endgroup$
    – S. Carnahan
    Jan 31, 2019 at 2:50

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