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 A086829 #13 Feb 16 2025 08:32:50
%S A086829 1,3,45360,2615348736000,1938901255416373248000000,
%T A086829 46499165848737652183499931018854400000000,
%U A086829 76035233004283445109031520415161922110944103922401280000000000
%N A086829 Number of n X n matrices on n^2 distinct symbols modulo rotations and reflections.
%C A086829 Also the number of distinct adjacency matrices on the n X n grid graph P_n x P_n. - _Eric W. Weisstein_, May 01 2017
%H A086829 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/AdjacencyMatrix.html">Adjacency Matrix</a>
%H A086829 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/GridGraph.html">Grid Graph</a>
%H A086829 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SquareMatrix.html">Square Matrix</a>
%F A086829 a(n) = (n^2)!/8, n>1. - _Vladeta Jovovic_, Aug 10 2003
%t A086829 Table[Piecewise[{{1, n == 1}}, (n^2)!/8], {n, 7}]
%Y A086829 Cf. A087074.
%K A086829 nonn,easy
%O A086829 1,2
%A A086829 _Eric W. Weisstein_, Aug 08 2003
%E A086829 More terms from _Sam Alexander_, Feb 27 2004