Repository logo
 

Search Results

Now showing 1 - 2 of 2
  • Ordinal sums of impartial games
    Publication . Carvalho, Alda; Neto, João; Santos, Carlos
    In an ordinal sum of two combinatorial games G and H, denoted by G : H, a player may move in either G (base) or H (subordinate), with the additional constraint that any move on G completely annihilates the component H. It is well-known that the ordinal sum does not depend on the form of its subordinate, but depends on the form of its base. In this work, we analyze g(G : H) where G and H are impartial forms, observing that the g-values are related to the concept of minimum excluded value of order k. As a case study, we introduce the ruleset OAK, a generalization of GREEN HACKENBUSH. By defining the operation gin sum, it is possible to determine the literal forms of the bases in polynomial time. (C) 2017 Elsevier B.V. All rights reserved.
  • Combinatorics of JENGA
    Publication . Carvalho, Alda; Neto, João; Santos, Carlos
    JENGA, a very popular game of physical skill, when played by perfect players, can be seen as a pure combinatorial ruleset. Taking that into account, it is possible to play with more than one tower; a move is made by choosing one of the towers, removing a block from there, that is, a disjunctive sum. JENGA is an impartial combinatorial ruleset, i.e., Left options and Right options are the same for any position and all its followers. In this paper, we illustrate how to determine the Grundy value of a JENGA tower by showing that it may be seen as a bidimensional vector addition game. Also, we propose a class of impartial rulesets, the clock nim games, JENGA being an example of that class.