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 A382018 #18 Aug 15 2025 15:55:04 %S A382018 1,1,4,33,908,85411,28227922,32597166327 %N A382018 Number of orbits under the action of the permutation group S(n) on the nonsingular n X n matrices over GF(2). %C A382018 The action is defined by f.M(i,j)=M(f(i),f(j)). %C A382018 Equivalently, the number of digraphs on n unlabeled nodes with loops allowed but no more than one arc with the same start and end node with adjacency matrices invertible over GF(2). %H A382018 Jens Emil Christensen, Søren Fuglede Jørgensen, Andreas Pavlogiannis, and Jaco van de Pol, <a href="https://doi.org/10.1007/978-3-031-97063-4_6">On Exact Sizes of Minimal CNOT Circuits</a>, RC 2025, LNCS, vol 15716, pp. 71-88; <a href="https://arxiv.org/abs/2503.01467">arXiv:2503.01467</a> [quant-ph], 2025, Table 1. %e A382018 For n = 2, representatives of the four different orbits are [[1, 0], [0, 1]], [[1, 1], [0, 1]], [[0, 1], [1, 1]], and [[0, 1], [1, 0]]. %Y A382018 Cf. A000595, A002884, A224879. %K A382018 nonn,hard,more %O A382018 0,3 %A A382018 _Søren Fuglede Jørgensen_, Mar 12 2025