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 A089674 #16 May 05 2025 20:33:52 %S A089674 0,0,0,1692,2329280,13441654352,190945826194432 %N A089674 a(n) = number of n X n (0,1) matrices A such that the 2n+2 vectors consisting of the rows and the columns of the matrix A, as well as the main diagonal read in the upward direction and the main antidiagonal, are all distinct. %Y A089674 Cf. A088310, A088616, A089673. %Y A089674 Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763 %K A089674 nonn,more %O A089674 1,4 %A A089674 _Vladeta Jovovic_, Jan 04 2004 %E A089674 a(6)-a(7) from _Bert Dobbelaere_, May 05 2025