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 A059504 #21 Jul 16 2021 19:59:57
%S A059504 10,12,13,14,15,16,17,18,19,22,1012,1013,1014,1015,1016,1017,1018,
%T A059504 1019,1021,1022,1210,1213,1214,1215,1216,1217,1218,1219,1310,1312,
%U A059504 1314,1315,1316,1317,1318,1319,1321,1322,1410,1412,1413,1415,1416,1417,1418,1419
%N A059504 Numbers k with the property that reading k gives correct, although not necessarily complete, information about itself.
%C A059504 This is another sequence of "self-describing" numbers.
%H A059504 G. C. Greubel, <a href="/A059504/b059504.txt">Table of n, a(n) for n = 1..1000</a>
%e A059504 Reading 1016 as "one 0, one 6", it states correctly that it contains one 0 and one 6.
%t A059504 A059504Q = Module[{i = IntegerDigits@#}, EvenQ@Length@i && SubsetQ[Reverse /@ Tally@i, Partition[i, 2]]] &; Select[Range@1419, A059504Q] (* _JungHwan Min_, Jan 15 2017 *)
%Y A059504 Cf. A109775.
%K A059504 base,nonn,word,nice
%O A059504 1,1
%A A059504 _Floor van Lamoen_, Jan 19 2001
%E A059504 More terms from _Jud McCranie_, Aug 13 2005