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 A184267 #19 Jan 20 2018 16:14:07 %S A184267 8,108,2192,52488,1342208,35792568,981706832,27487816992,781874936816, %T A184267 22517998808448,655069036708592,19215358428046176,567592125344909792, %U A184267 16865594582168158776,503719091506096394752,15111572745196608608736,455125014443154512836736 %N A184267 Number of distinct n X 5 toroidal binary arrays. %H A184267 Vaclav Kotesovec, <a href="/A184267/b184267.txt">Table of n, a(n) for n = 1..660</a> %H A184267 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 A184267 a(n) ~ 32^n / (5*n). - _Vaclav Kotesovec_, Sep 04 2014 %p A184267 with(numtheory): %p A184267 a:= n-> add(add(phi(c)*phi(d) *2^(5*n/ilcm(c, d)), %p A184267 d=divisors(n)), c=[1,5])/(5*n): %p A184267 seq(a(n), n=1..25); # _Alois P. Heinz_, Aug 25 2012 %Y A184267 Column 5 of A184271. %K A184267 nonn %O A184267 1,1 %A A184267 _R. H. Hardin_, Jan 10 2011 %E A184267 More terms from _Alois P. Heinz_, Aug 25 2012