Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #9 Aug 27 2024 14:57:40
%S 20,491,7502,52013,297464,1119791,3900890,11135201,29329232
%N The number of distinct planes defined by an n X n X n grid of points.
%e The 8 points of the 2 X 2 X 2 grid define 20 planes: the 6 faces of the cube, 6 planes formed by an edge and its opposite edge, and 8 planes defined by the three vertices surrounding a given vertex. So, a(2)=20.
%Y Cf. A222267, A270579.
%K nonn,more
%O 2,1
%A _Clive Tooth_, Mar 19 2016