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 A184265 #22 Jan 20 2018 16:13:21 %S A184265 4,14,64,352,2192,14624,99880,699252,4971184,35792568,260301176, %T A184265 1908882592,14096303344,104715443852,781874941184,5864062367252, %U A184265 44152937528384,333599974922264,2528336632928152,19215358428046176,146402730743992960,1117984489446008100 %N A184265 Number of distinct n X 3 toroidal binary arrays. %H A184265 Vaclav Kotesovec, <a href="/A184265/b184265.txt">Table of n, a(n) for n = 1..1000</a> %H A184265 S. N. Ethier, <a href="http://arxiv.org/abs/1301.2352">Counting toroidal binary arrays</a>, arXiv preprint arXiv:1301.2352, 2013 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Ethier/ethier2.html">J. Int. Seq. 16 (2013) #13.4.7</a> . %F A184265 a(n) ~ 8^n / (3*n). - _Vaclav Kotesovec_, Sep 04 2014 %p A184265 with(numtheory): %p A184265 a:= n-> add(add(phi(c)*phi(d) *2^(3*n/ilcm(c, d)), %p A184265 d=divisors(n)), c=[1, 3])/(3*n): %p A184265 seq(a(n), n=1..30); # _Alois P. Heinz_, Aug 25 2012 %Y A184265 Column 3 of A184271. %K A184265 nonn %O A184265 1,1 %A A184265 _R. H. Hardin_, Jan 10 2011 %E A184265 More terms from _Alois P. Heinz_, Aug 25 2012