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