English

A $q$-Queens Problem. VI. The Bishops' Period

Combinatorics 2021-06-21 v4

Abstract

The number of ways to place qq nonattacking queens, bishops, or similar chess pieces on an n×nn\times n square chessboard is essentially a quasipolynomial function of nn (by Part I of this series). The period of the quasipolynomial is difficult to settle. Here we prove that the empirically observed period 2 for three to ten bishops is the exact period for every number of bishops greater than 2. The proof depends on signed graphs and the Ehrhart theory of inside-out polytopes.

Cite

@article{arxiv.1405.3001,
  title  = {A $q$-Queens Problem. VI. The Bishops' Period},
  author = {Thomas Zaslavsky and Seth Chaiken and Christopher R. H. Hanusa},
  journal= {arXiv preprint arXiv:1405.3001},
  year   = {2021}
}

Comments

15 pp.; 12 pp. without white space. v2: Updated citations, rearranged authors. 12 pp. v3: Updated citations. Rm unnec special commands. v4: 13 pp. Rev title. Corrected error; rev abstract; minor rev

R2 v1 2026-06-22T04:12:33.585Z