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 A057578 #22 Feb 08 2022 03:35:48 %S A057578 1,1,1,3,9,18,38 %N A057578 Maximal numbers of codewords in ternary code of length n with Hamming distance 3. %H A057578 Patric R. J. Östergård, <a href="https://users.aalto.fi/~pat/23.html">Classification of small binary/ternary one-error-correcting codes (Appendix)</a>, Discrete Mathematics 223 (2000), 253-262. %Y A057578 Cf. A057574-A057584, A050142. %K A057578 nonn,more %O A057578 0,4 %A A057578 _N. J. A. Sloane_, Oct 04 2000