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%I #28 Jun 25 2017 20:23:15
%S 1,6,265,126140,855966441,102526835994056,258081861682902430193
%N Number of oriented (0, 1, 2)-factors of the Johnson graph J(n, 2).
%C From _James East_, Jul 13 2016: (Start)
%C a(5) and a(6) were calculated by James Mitchell using the GAP System Packages Semigroups (see link).
%C a(n) is also the number of minimal size all-idempotent generating sets for the singular part of the Brauer monoid (see East-Gray paper). (End)
%H J. East, R. D. Gray, <a href="http://arxiv.org/abs/1404.2359">Diagram monoids and Graham-Houghton graphs: idempotents and generating sets of ideals</a>, arXiv:1404.2359 [math.GR], 2014.
%H GAP, <a href="http://www.gap-system.org/Packages/semigroups.html">Semigroups</a>
%H Ronald Niles, <a href="https://github.com/RonNiles/Computation-of-A244493">C++ project on GitHub</a>
%H Ronald Niles, <a href="/A244493/a244493_1.pdf">Computation of A244493</a>
%o (C++) See Niles link.
%K nonn,more
%O 2,2
%A _N. J. A. Sloane_, Jul 05 2014
%E Name clarified by _James East_, Jul 14 2016
%E a(6) corrected and a(7) added by _Ronald Niles_, Apr 21 2017
%E a(8) added by _Ronald Niles_, Jun 25 2017
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