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 A229086 #19 Nov 28 2021 02:50:33 %S A229086 1,3,7,11,19,31,43,67,103,127,131,199,239,307,331,379,439,463,547,683, %T A229086 887,911,991,1123,1171,1291,1531,1543,1783,1951,2731,2843,3067,3079, %U A229086 3511,3823,4099,5107,5323,5419,5659,5851,6151,6343,6679,6871,6967,7159,8191 %N A229086 Numbers k such that the concatenation of the divisors of k written in base 2 is a palindromic number. %C A229086 Concatenation of the divisors of n written in base 2 = A182621. %C A229086 Are there composite numbers with this property? %C A229086 Conjecture: a(n) for n > 1 is not equal to A161387, sequence also contains composites. %C A229086 The answer to the question above is Yes. The first two composites are 297883 and 476635. - _T. D. Noe_, Sep 17 2013 %H A229086 Amiram Eldar, <a href="/A229086/b229086.txt">Table of n, a(n) for n = 1..10000</a> %e A229086 The number 103 is in sequence because the concatenation of its divisors written in base 2 (1, 1100111) is palindromic number - 11100111. %t A229086 Select[Range[10000], (temp=Flatten[IntegerDigits[Divisors[#],2]]; temp==Reverse[temp])&] %Y A229086 Cf. A161387, A182621. %K A229086 nonn,base %O A229086 1,2 %A A229086 _Jaroslav Krizek_, Sep 13 2013