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 A282427 #29 Aug 12 2022 09:17:30 %S A282427 1,3,7,39,47,111,959,3319,7407,11967,13007,16239 %N A282427 Numbers k such that A282442(k) = ceiling(k/2) + 1. %C A282427 All terms are odd. %C A282427 Proof: if A282442(2m) = m + 1, then the step of length m would have to have concluded on exactly the middle step, but a phase with step-length m cannot end on the middle step because the distance from the middle step to the top/bottom of the staircase is equal to m. %H A282427 Mathematics Stack Exchange user Sheljohn, <a href="http://math.stackexchange.com/questions/2145924">A curious sequence</a>. %Y A282427 Cf. A282442. %K A282427 nonn,more %O A282427 1,2 %A A282427 _Peter Kagey_, Feb 15 2017