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 A053994 #7 Jul 12 2018 20:27:57 %S A053994 1,0,1,1,0,2,11,0,97,354,0,31381,395551,0,90120677 %N A053994 Nonattacking queens on a 2n+1 X 2n+1 toroidal board, solutions which differ only by rotation, reflection or torus shift count only once. %D A053994 A. P. Street and R. Day, Sequential binary arrays II: Further results on the square grid, pp. 392-418 of Combinatorial Mathematics IX. Proc. Ninth Australian Conference (Brisbane, August 1981). Ed. E. J. Billington, S. Oates-Williams and A. P. Street. Lecture Notes Math., 952. Springer-Verlag, 1982 (for getting equivalence classes). %H A053994 I. Rivin, I. Vardi and P. Zimmermann, <a href="https://www.jstor.org/stable/2974691">The n-queens problem</a>, Amer. Math. Monthly, 101 (1994), 629-639 (for finding the solutions). %Y A053994 A007705, A006841, A051906. %K A053994 hard,nice,nonn %O A053994 0,6 %A A053994 _Matthias Engelhardt_, Apr 05 2000 %E A053994 More terms from _Matthias Engelhardt_, Jan 11 2001