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 A364504 #31 Apr 14 2025 15:05:20 %S A364504 1,0,2,30,1352,226922,128441094,267855152858,1990875917805852, %T A364504 52918918728713551244,5046393600526600826576990, %U A364504 1722423352379200292770200349728,2106175531602971710801901685263906946,9224774497259881798661234516031754156588512,144713995908210595144464778124853904625705818728754 %N A364504 Number of tilings of an n X n square using dominoes and trominoes (of any shape). %H A364504 David Radcliffe, <a href="/A364504/b364504.txt">Table of n, a(n) for n = 0..17</a> (computed by Liang Kai). %H A364504 Liang Kai, <a href="https://arxiv.org/abs/2503.17698">Solving tiling enumeration problems by tensor network contractions</a>, arXiv:2503.17698 [math.CO], 2025. %H A364504 Liang Kai, <a href="https://github.com/liang-kai-ruqi/tiling">Tiling</a>, GitHub repository. %H A364504 Wikipedia, <a href="https://en.wikipedia.org/wiki/Domino_(mathematics)">Domino (mathematics)</a> %H A364504 Wikipedia, <a href="https://en.wikipedia.org/wiki/Tromino">Tromino</a> %F A364504 a(n) = A364457(n,n). %Y A364504 Main diagonal of A364457. %Y A364504 Cf. A219874, A219994. %K A364504 nonn %O A364504 0,3 %A A364504 _Alois P. Heinz_, Jul 26 2023 %E A364504 Terms n>=4 had to be corrected as was pointed out by _Martin Fuller_ and _David Radcliffe_ - _Alois P. Heinz_, Apr 05 2025 %E A364504 a(13)-a(17) from _David Radcliffe_, Apr 07 2025