×

Playing Bynum’s game cautiously. (English) Zbl 1490.91036

Summary: Several sequences of infinitesimals are introduced for the purpose of analyzing a restricted form of Bynum’s game or “Eatcake”. Two of these have terms with uptimal values (à la Conway and Ryba, 1970s). All others (eight) are specified by “uptimal+ forms,” i.e., standard uptimals plus a fractional uptimal. The game itself is played on an \(n \times m\) grid of unit squares, and here we describe all followers (submatrices) of the \(12 \times 12\) grid. Positional values of larger grids become intractable. However, an examination of \(n \times n\) squares, \(2 \leq n \leq 21\), reveals that all but three of them are equal to \(\ast \), the exceptions being the \(10\times10\), \(14\times14\), and \(18\times18\) cases. Nonetheless, the exceptional cases have “star-like” characteristics: they are of the form \(\pm (G)\), confused with both zero and up, and less than double-up.

MSC:

91A46 Combinatorial games

Software:

CGSuite

References:

[1] M. H. Albert, R J. Nowakowski, and D. Wolfe, Lessons in Play, An Introduction to Combinatorial Game Theory. CRC Press, 2 nd edition, Boca Raton, FL. · Zbl 1410.91001
[2] E. R. Berlekamp, J. H. Conway, and R. K. Guy, Winning Ways. A. K. Peters, Ltd., Wellesley, MA, 2 nd edition 2001.
[3] J. H. Conway, On Numbers and Games. A. K. Peters, Ltd., Natick, MA, 2 nd . edition 2001. · Zbl 0972.11002
[4] A. Fraenkel, Complexity, appeal and complexity of combinatorial games, Theo-ret. Comput. Sci., 313(3): 393-415, February 2004. · Zbl 1066.91017
[5] R. K. Guy, Fair game, COMAP Mathematics Exploration Series, 1989.
[6] L. R. Haff and W. J. Garner, An Introduction to Combinatorial Game Theory. Lulu Press, 2018.
[7] N. A. McKay, Canonical Forms of uptimals, Theoret. Comput. Sci., 412(2011): 7122-7132, 2011. · Zbl 1229.91088
[8] R. Nowakowski, editor, Games of No Chance, Combinatorial Games at MSRI, 1994. Cambridge University Press, MSRI Publications 29, 1996.
[9] A. N. Siegel, CGSuite. Combinatorial games suite computer program, 2004
[10] A. N. Siegel, Combinatorial Game Theory. American Mathematical Society, Graduate Studies in Mathematics. Vol. 146, Providence, RI, 2013. · Zbl 1288.91003
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.