This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A279405 #24 Jun 16 2024 15:22:21 %S A279405 0,0,0,2,2,4,4,8,7,12,10,18 %N A279405 Peaceable coexisting armies of queens on a torus: the maximum number m such that m white queens and m black queens can coexist on an n X n toroidal chessboard without attacking each other. %C A279405 a(n) <= A250000(n). %C A279405 a(n) is maximal m such that A279406(n,m) >= m. %H A279405 Andy Huchala, <a href="/A279405/a279405_4.py.txt">Python program</a>. %H A279405 Katie Clinch, Matthew Drescher, Tony Huynh, and Abdallah Saffidine, <a href="https://www.arxiv.org/abs/2406.06974">Constructions, bounds, and algorithms for peaceable queens</a>, arXiv:2406.06974 [math.CO], 2024. See p. 1. %e A279405 A solution for n=6: %e A279405 ...... %e A279405 .W...W %e A279405 ...B.. %e A279405 ..B.B. %e A279405 ...B.. %e A279405 .W...W %Y A279405 Cf. A250000, A279406. %K A279405 nonn,hard,more %O A279405 1,4 %A A279405 _Andrey Zabolotskiy_, Dec 11 2016 %E A279405 a(10)-a(12) from _Andy Huchala_, Mar 10 2024