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 A112578 #8 Sep 08 2013 02:57:13 %S A112578 0,8,900,359424,370828800,820150272000,3435918974208000, %T A112578 24957654229057536000,294060698786444083200000, %U A112578 5334667831784096818790400000,42889554205720574193041408000000 %N A112578 Number of indecomposable 3-D arrays of 0's and 1's with plane sums 2. %D A112578 P. J. Cameron and T. W. Mueller, Decomposable functors and the exponential principle, II, in preparation %H A112578 P. J. Cameron and T. W. Mueller, <a href="http://arxiv.org/abs/0911.3760v2">Decomposable functors and the exponential principle, II</a>, arXiv:0911.3760 [math.CO] %F A112578 a(1)=0, a(n) = (n!)^2*b(n)/2^n for n>1, where b(0)=1 and sum (n-1 choose k-1)*((2n-2k-1)!!)^2*b(k) = ((2n-1)!!)^2. %e A112578 a(2)=8: six pairs of opposite edges and two inscribed tetrahedra. %Y A112578 Cf. A010796 (2-D case), A112579, A112580. %K A112578 nonn,easy %O A112578 1,2 %A A112578 _Peter J. Cameron_, Sep 14 2005