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 A093989 #11 Jan 13 2023 09:17:59 %S A093989 1,1,6,35,290,2714,27524,291073,3166124,35169275,397047529,4541672859, %T A093989 52510998347 %N A093989 Number of free n-celled polyzebras (or zebra-move-connected polyominoes). %C A093989 A polyzebra is a (2,3) leaper. A polyzebra need not be connected in the usual edge-connected sense. %Y A093989 Cf. A093877, A093990, A093991, A093992, A030444. %K A093989 nonn,more %O A093989 1,3 %A A093989 _Joseph Myers_, May 25 2004