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 A144193 #14 Aug 07 2018 20:53:33 %S A144193 0,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0 %N A144193 Square array (5 X 5) read by rows. %C A144193 Permutation contributing to the determinant that gives the 5th value of the moebius function. Determinant of matrix is equal to -1. The array is symmetrical. %H A144193 J. Davies, <a href="https://web.archive.org/web/20171111153945/http://juliusdavies.ca:80/andre/permutations.html">Permutation Calculator</a> %H A144193 Herbert S. Wilf, <a href="https://arxiv.org/abs/math/0408263">The Redheffer matrix of a partially ordered set</a>, arXiv:math/0408263 [math.CO], 2004. %e A144193 The array is: %e A144193 0,0,0,0,1 %e A144193 0,1,0,0,0 %e A144193 0,0,1,0,0 %e A144193 0,0,0,1,0 %e A144193 1,0,0,0,0 %Y A144193 Cf. A143104, A002033. %K A144193 fini,full,nonn,tabf %O A144193 1,1 %A A144193 _Mats Granvik_, Sep 13 2008