English

Cyclic impartial games with carry-on moves

Combinatorics 2025-12-17 v1

Abstract

In an impartial combinatorial game, both players have the same options in the game and all its subpositions. The classical Sprague-Grundy Theory was developed for short impartial games, where players have a finite number of options, there are no special moves, and an infinite run is not possible. Subsequently, many generalizations have been proposed, particularly the Smith-Frankel-Perl Theory devised for games where the infinite run is possible, and the Larsson-Nowakowski-Santos Theory able to deal with entailing moves that disrupt the logic of the disjunctive sum. This work presents a generalization that combines these two theories, suitable for analyzing cyclic impartial games with carry-on moves, which are particular cases of entailing moves where the entailed player has no freedom of choice in their response. This generalization is illustrated with sc green-lime hackenbush, a game inspired by the classic green hackenbush.

Keywords

Cite

@article{arxiv.2512.14466,
  title  = {Cyclic impartial games with carry-on moves},
  author = {Tomoaki Abuku and Alda Carvalho and Urban Larsson and Richard J. Nowakowski and Carlos P. Santos and Koki Suetsugu},
  journal= {arXiv preprint arXiv:2512.14466},
  year   = {2025}
}

Comments

37 pages, 16 figures

R2 v1 2026-07-01T08:27:29.292Z