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 A226816 #5 Jun 19 2013 13:36:07
%S A226816 2,4,8,10,16,28,34,50,52,58,76,82,88,130,244,250,292,344,346,352,370,
%T A226816 424,586,730,736,778,1072,2188,2194,2236,2402,2404,2410,2428,2482,
%U A226816 2530,2644,3130,4588,6562,6568,6610,6904,8962,16808,16810,16816,16834,16888
%N A226816 Numbers of the form 3^j + 7^k, for j and k >= 0.
%H A226816 T. D. Noe, <a href="/A226816/b226816.txt">Table of n, a(n) for n = 1..10000</a>
%t A226816 a = 3; b = 7; mx = 20000; Union[Flatten[Table[a^n + b^m, {m, 0, Log[b, mx]}, {n, 0, Log[a, mx - b^m]}]]]
%Y A226816 Cf. A004050 (2^j + 3^k), A226806-A226832 (cases to 8^j + 9^k).
%Y A226816 Cf. A226791 ((3^j + 7^k)/2).
%K A226816 nonn
%O A226816 1,1
%A A226816 _T. D. Noe_, Jun 19 2013