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 A287228 #13 Feb 16 2025 08:33:46 %S A287228 1,1,1,27,2376,298062,66426798,47833036802,119487298588717, %T A287228 857547047985463278 %N A287228 Number of matchings in the n-triangular honeycomb obtuse knight graph. %H A287228 Stan Wagon, <a href="http://www.jstor.org/stable/10.4169/college.math.j.45.4.278">Graph Theory Problems from Hexagonal and Traditional Chess</a>, The College Mathematics Journal, Vol. 45, No. 4, September 2014, pp. 278-287. %H A287228 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IndependentEdgeSet.html">Independent Edge Set</a> %H A287228 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Matching.html">Matching</a> %Y A287228 Cf. A287229, A287230. %K A287228 nonn,more %O A287228 1,4 %A A287228 _Eric W. Weisstein_, May 22 2017 %E A287228 a(9)-a(10) from _Andrew Howroyd_, Jul 17 2017