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 A387227 #14 Aug 29 2025 10:14:52 %S A387227 3,48,1165688832,2104020352700472395232386541930940465152 %N A387227 Number of Hamiltonian cycles in the n-Sierpinski tetrahedron graph. %C A387227 a(3) from Table 1 in Knuth. %H A387227 Pontus von Brömssen, <a href="/A387227/b387227.txt">Table of n, a(n) for n = 1..5</a> %H A387227 Donald E. Knuth, "Hamiltonian Paths and Cycles." <a href="https://www-cs-faculty.stanford.edu/~knuth/fasc8a.ps.gz">Volume 4, Pre-Fascicle 8A in The Art of Computer Programming.</a> Draft. Aug. 19, 2025. %H A387227 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HamiltonianCycle.html">Hamiltonian Cycle</a>. %H A387227 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SierpinskiTetrahedronGraph.html">Sierpinski Tetrahedron Graph</a>. %Y A387227 Cf. A246959. %K A387227 nonn,hard,new %O A387227 1,1 %A A387227 _Eric W. Weisstein_, Aug 23 2025 %E A387227 a(4)-a(5) from _Pontus von Brömssen_, Aug 24 2025