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 A160962 #8 Oct 16 2024 09:20:03 %S A160962 12,130,13300,1333000,1333333000000,13333333300000000, %T A160962 1333333333000000000,1333333333333333000000000000000, %U A160962 1333333333333333333333333333333000000000000000000000000000000 %N A160962 Perfect numbers written in base 4. %H A160962 Amiram Eldar, <a href="/A160962/b160962.txt">Table of n, a(n) for n = 1..14</a> %F A160962 a(n) = A007090(A000396(n)). - _Amiram Eldar_, Oct 16 2024 %t A160962 Map[FromDigits[IntegerDigits[#, 4]] &, PerfectNumber[Range[10]]] (* _Amiram Eldar_, Oct 16 2024 *) %Y A160962 Cf. A000043, A000396, A000668, A135650, A161322. %K A160962 nonn,base %O A160962 1,1 %A A160962 Vladislav-Stepan Malakhovsky and _Juri-Stepan Gerasimov_, May 31 2009 %E A160962 Edited by _N. J. A. Sloane_, Jun 07 2009