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 A375141 #21 Sep 03 2024 01:42:38 %S A375141 1,1,1,4,40,5856,8609280 %N A375141 Number of even reduced Latin squares of order n. %H A375141 Carolin Hannusch, <a href="https://arato.inf.unideb.hu/hannusch.carolin/evenlatinsquares.txt">Python program for latin squares</a> %F A375141 a(n) + A375121(n) = A000315(n). %e A375141 n=4: [[1, 2, 3, 4], [2, 1, 4, 3], [3, 4, 1, 2], [4, 3, 2, 1]]; %e A375141 [[1, 2, 3, 4], [2, 1, 4, 3], [3, 4, 2, 1], [4, 3, 1, 2]]; %e A375141 [[1, 2, 3, 4], [2, 3, 4, 1], [3, 4, 1, 2], [4, 1, 2, 3]]; %e A375141 [[1, 2, 3, 4], [2, 4, 1, 3], [3, 1, 4, 2], [4, 3, 2, 1]] %Y A375141 Cf. A000315, A375121. %K A375141 nonn,more,hard %O A375141 1,4 %A A375141 _Carolin Hannusch_, Jul 31 2024