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 A137888 #17 Feb 16 2025 08:33:07 %S A137888 0,2,24,13824,47421358080 %N A137888 Number of directed Hamiltonian paths in the n-halved cube graph. %H A137888 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HalvedCubeGraph.html">Halved Cube Graph</a> %H A137888 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HamiltonianPath.html">Hamiltonian Path</a> %F A137888 a(n) = 2 * A308130(n). %Y A137888 Cf. A308130. %K A137888 nonn,more %O A137888 1,2 %A A137888 _Eric W. Weisstein_, Feb 20 2008 %E A137888 a(5) from _Max Alekseyev_, Dec 13 2011