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 A057581 #11 Feb 02 2020 21:41:36 %S A057581 2,3,6,18,42 %N A057581 Maximal numbers of codewords in mixed code with 3 binary coordinates and n ternary coordinates with Hamming distance 3. %H A057581 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 A057581 Cf. A057574-A057584, A050142. %K A057581 nonn,more %O A057581 0,1 %A A057581 _N. J. A. Sloane_, Oct 04 2000