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 A089458 #11 Oct 05 2022 16:55:21
%S A089458 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,64,2131,38022,480713,
%T A089458 4872679,42360239
%N A089458 Number of n-celled polyominoes with exactly 6 holes.
%H A089458 Tomás Oliveira e Silva, <a href="http://sweet.ua.pt/tos/animals/a44.html">Animal enumerations on the {4,4} Euclidean tiling</a>
%Y A089458 Cf. A001419, A000104, A057418, A089454, A089455, A089456, A089457.
%K A089458 nonn,hard,more
%O A089458 1,23
%A A089458 _Joseph Myers_, Nov 04 2003
%E A089458 a(27)-a(28) from Tomás Oliveira e Silva's page added by _Andrey Zabolotskiy_, Oct 02 2022