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 A352478 #14 Mar 27 2022 13:38:46 %S A352478 1,2,3,6,4,2,2,2,2,2,2,12 %N A352478 a(n) is the number of Toeplitz anti-Hadamard matrices of order n whose sum of the inverse squares of their singular values is maximal. %C A352478 Conjecture: a(1) = 1 and a(3) = 3 are the only odd terms. %H A352478 R. L. Graham and N. J. A. Sloane, <a href="http://dx.doi.org/10.1016/0024-3795(84)90090-9">Anti-Hadamard matrices</a>, Linear Alg. Applic., 62 (1984), 113-137. %Y A352478 Cf. A351821. %Y A352478 Cf. A005312, A005313, A351984, A352177. %K A352478 nonn,hard,more %O A352478 1,2 %A A352478 _Stefano Spezia_, Mar 17 2022