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 A165784 #7 Mar 11 2014 01:32:48 %S A165784 1,5,7,85,93,119,127,21845,21973,23901,24029,30583,30711,32639,32767, %T A165784 1431655765,1431688533,1440044501,1440077269,1566399837,1566432605, %U A165784 1574788573,1574821341,2004318071,2004350839,2012706807,2012739575 %N A165784 a(1)=1. For n >= 2, each a(n) = the decimal equivalent of either a(k)U0Ua(k) or a(k)U1Ua(k), where U denotes concatenation of the binary representations of the arguments, and where k is some positive integer < n. The numbers are arranged in numerical order. %C A165784 Each term is a palindrome when written in base 2. %Y A165784 Cf. A165785 %K A165784 base,nonn %O A165784 1,2 %A A165784 _Leroy Quet_, Sep 26 2009 %E A165784 More terms from _Sean A. Irvine_, Dec 03 2009