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 A251547 #14 May 15 2018 16:44:23 %S A251547 1,2,2,3,3,3,3,3,3,5,5,5,5,5,5,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,12,12,15, %T A251547 15,15,15,15,15,19,19,20,20,20,20,20,20,20,23,23,23,23,23,23,23,23,27, %U A251547 27,27,27,27,27,27,27,27,27 %N A251547 A251546(n)/2. %H A251547 Chai Wah Wu, <a href="/A251547/b251547.txt">Table of n, a(n) for n = 1..10000</a> %H A251547 David L. Applegate, Hans Havermann, Bob Selcoe, Vladimir Shevelev, N. J. A. Sloane, and Reinhard Zumkeller, <a href="http://arxiv.org/abs/1501.01669">The Yellowstone Permutation</a>, arXiv preprint arXiv:1501.01669, 2015 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL18/Sloane/sloane9.html">J. Int. Seq. 18 (2015) 15.6.7</a>. %o A251547 (Haskell) %o A251547 a251547 = flip div 2 . a251546 -- _Reinhard Zumkeller_, Dec 19 2014 %Y A251547 Cf. A098550, A247253, A251416, A251417, A251546-A251552. %K A251547 nonn %O A251547 1,2 %A A251547 _N. J. A. Sloane_, Dec 18 2014