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%I #33 Feb 14 2013 14:18:55
%S 1,3,123,14632581
%N a(n) = number of distinct ways to choose a subset of the n*2^(n-1) edges of the n-cube so that the resulting figure is connected and fully n-dimensional.
%C "Distinct" means that figures differing by a rotation are not regarded as different.
%C "Fully n-dimensional" means not lying in a proper subspace.
%C Suggested by Sol LeWitt's work "Variations of Incomplete Open Cubes," which shows 122 of the 123 figures in the three-dimensional case.
%D Peter Schjeldahl, Less is beautiful, The Art World, The New Yorker, March 13, 2000, pp. 98-99.
%H Sol LeWitt, <a href="http://25.media.tumblr.com/tumblr_masbbafJ4K1rf1adro1_1280.jpg">Variations of Incomplete Open Cubes</a> [The full cube itself is not included in his list.]
%H Andrew Weimholt, <a href="/A222186/a222186.dat.txt">3D solutions in numerical representation</a>
%H Andrew Weimholt, <a href="/A222186/a222186_1.dat.txt">Notes on reading the 3D solutions</a>
%H Andrew Weimholt, <a href="/A222186/a222186.cpp.txt">C++ program for A222186 and A222192</a>
%e For n=2 the three figures are: the four edges of a square, or omit one edge, or omit two adjacent edges.
%Y Cf. A222192.
%K nonn,bref,more
%O 1,2
%A _N. J. A. Sloane_, Feb 11 2013
%E a(3) confirmed by _Andrew Weimholt_, Feb 12 2013
%E a(4) computed by _Andrew Weimholt_, Feb 13 2013
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