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 A226821 #3 Jun 19 2013 02:27:21
%S A226821 2,4,9,10,11,17,28,35,65,67,73,82,89,91,145,244,251,307,513,515,521,
%T A226821 539,593,730,737,755,793,1241,2188,2195,2251,2699,4097,4099,4105,4123,
%U A226821 4177,4339,4825,6283,6562,6569,6625,7073,10657,19684,19691,19747,20195,23779
%N A226821 Numbers of the form 3^j + 8^k, for j and k >= 0.
%H A226821 T. D. Noe, <a href="/A226821/b226821.txt">Table of n, a(n) for n = 1..10000</a>
%t A226821 a = 3; b = 8; mx = 25000; Union[Flatten[Table[a^n + b^m, {m, 0, Log[b, mx]}, {n, 0, Log[a, mx - b^m]}]]]
%Y A226821 Cf. A004050 (2^j + 3^k), A226806-A226832 (cases to 8^j + 9^k).
%K A226821 nonn
%O A226821 1,1
%A A226821 _T. D. Noe_, Jun 19 2013