Theoretical Computer Science ( IF 0.9 ) Pub Date : 2021-06-30 , DOI: 10.1016/j.tcs.2021.06.032 Oren Friman , Gabriel Nivasch
Let S be a set of positive integers, and let D be a set of integers larger than 1. The game is an impartial combinatorial game introduced by Sopena (2016), which is played with a single pile of tokens. In each turn, a player can subtract from the pile, or divide the size of the pile by , if the pile size is divisible by d. Sopena partially analyzed the games with and for , but left the case open.
We solve this problem by calculating the Sprague–Grundy function of for , for all . We also calculate the Sprague–Grundy function of for all k, and show that it exhibits similar behavior. Finally, following Sopena's suggestion to look at games with , we derive some partial results for the game , whose Sprague–Grundy function seems to behave erratically and does not show any clear pattern. We prove that each value occurs infinitely often in its SG sequence, with a maximum gap length between consecutive appearances.
中文翻译:
一些 i-Mark 游戏
让S是一组正整数,让D是一组大于 1 的整数。 游戏
是 Sopena (2016) 推出的一种公正的组合游戏,使用单堆令牌进行游戏。在每一回合中,玩家可以减去 从桩,或将桩的大小除以 , 如果桩的大小可以被d整除。Sopena 部分分析了游戏 和 为了 ,但离开了这个案子 打开。我们通过计算 Sprague-Grundy 函数来解决这个问题
为了 , 对所有人 . 我们还计算了 Sprague-Grundy 函数对于所有k,并表明它表现出相似的行为。最后,按照 Sopena 的建议看游戏,我们为游戏推导出了一些部分结果 ,其 Sprague-Grundy 函数似乎表现不规则,并且没有显示任何清晰的模式。我们证明每个值 在其 SG 序列中无限频繁地出现,连续出现之间具有最大间隙长度。