Tiny and miny are operators that yield infinitesimal values when applied to numbers in combinatorial game theory. Given a positive number G, tiny G (denoted by in many texts) is equal to {0||0|-G} for any game G, whereas miny G (analogously denoted ) is tiny G’s negative, or {G|0||0}.
Tiny and miny aren’t just abstract mathematical operators on combinatorial games: tiny and miny games do occur “naturally” in such games as toppling dominoes. Specifically, tiny n, where n is a natural number, can be generated by placing two black dominoes outside n+2 white dominoes.
Tiny games and up have certain curious relational characteristics. Specifically, though is infinitesimal with respect to ↑ for all positive values of x, is equal to up. Expansion of into its canonical form yields {0||||||0|||||0||0|-G|||0||||0}. While the expression appears daunting, some careful and persistent expansion of the game tree of + ↓ will show that it is a second player win, and that, consequently, ↑. Similarly curious, Conway noted, calling it “amusing,” that “↑ is the unique solution of .” Conway’s assertion is also easily verifiable with canonical forms and game trees.
References edit
- Albert, Michael H.; Nowakowski, Richard J.; Wolfe, David (2007). Lessons in Play: An Introduction to Combinatorial Game Theory. A K Peters, Ltd. ISBN 1-56881-277-9.
{{cite book}}: Cite has empty unknown parameter:|1=(help) - Berlekamp, Elwyn R.; Conway, John H.; Guy, Richard K. (2003). Winning Ways for Your Mathematical Plays. A K Peters, Ltd.