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 A048518 #30 Jun 20 2021 17:15:42 %S A048518 1999,9199,338383,383833,1181881,1881181,1881811,2222929,2922229, %T A048518 8118181,8188111,8881111,9222229,15551551,15555151,15555511,16166611, %U A048518 16616161,33333373,33733333,34434343,44334343,44343433,51155551,51515551,55155151,55155511,55515151 %N A048518 Primes containing only two distinct digits whose sum of digits is 28, the second perfect number. %C A048518 Calculated by Robert T. McQuaid (robert.mcquaid(AT)headwaters.com). %H A048518 Alois P. Heinz, <a href="/A048518/b048518.txt">Table of n, a(n) for n = 1..21755</a> (first 200 terms from Sean A. Irvine) %H A048518 C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_035.htm">Source</a> from Carlos Rivera's Puzzle Site. %t A048518 Select[Prime[Range[3100000]],Count[DigitCount[#],0]==8&&Total[ IntegerDigits[ #]]==28&] (* _Harvey P. Dale_, Jun 11 2016 *) %Y A048518 Cf. A000396, A030291, A048517. %K A048518 nonn,base %O A048518 1,1 %A A048518 _Patrick De Geest_, May 15 1999 %E A048518 More terms from _Naohiro Nomoto_, Jul 28 2001 %E A048518 Offset corrected by _Sean A. Irvine_, Jun 20 2021