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 A238117 #12 Jun 30 2023 07:46:39 %S A238117 1,4,14,40,120,320,946,2496,7418,19616 %N A238117 Number of states with reflective symmetry arising in matrix method for enumerating Hamiltonian cycles on 2n X 2n grid. %H A238117 Ed Wynn, <a href="http://arxiv.org/abs/1402.0545">Enumeration of nonisomorphic Hamiltonian cycles on square grid graphs</a>, arXiv preprint arXiv:1402.0545 [math.CO], 2014. %Y A238117 Cf. A003763, A143246, A209077, A222065, A238115, A238116, A238118. %K A238117 nonn,more %O A238117 1,2 %A A238117 _N. J. A. Sloane_, Mar 05 2014