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 A165785 #21 Nov 10 2017 02:28:28 %S A165785 0,1,3,5,7,15,27,31,45,63,85,93,119,127,255,495,511,891,1023,1755, %T A165785 1787,2015,2047,2925,4095,5805,5869,8127,8191,10965,11997,15351,16383, %U A165785 21845,21973,23901,24029,30583,30711,32639,32767,65535,130815,131071,253935 %N A165785 Base 10 representation of A240602. %C A165785 Each term is a palindrome when written in base 2. %C A165785 This entry is the result of merging two sequences. The old definition (which did not have the initial zero) was: "a(1)=1. For n >= 2, each a(n) = the decimal equivalent of either a(k)Ua(k) or 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." %H A165785 Lior Manor, <a href="/A165785/b165785.txt">Table of n, a(n) for n = 1..1000</a> %t A165785 Select[Range[2^14], And[PalindromeQ@ Take[#, Floor[Length[#]/2]], PalindromeQ[#]] &@ IntegerDigits[#, 2] &] (* _Michael De Vlieger_, Nov 08 2017 *) %Y A165785 Cf. A165784, A240602. %K A165785 base,nonn %O A165785 1,3 %A A165785 _Leroy Quet_, Sep 26 2009 %E A165785 Extended by _Ray Chandler_, Mar 12 2010 %E A165785 New definition from _Lior Manor_, May 27 2014 %E A165785 Edited by _N. J. A. Sloane_, May 30 2014