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 A192200 #7 Oct 21 2019 19:14:50
%S A192200 0,4,8,56,76,80,104,604,704,724,728,3436,5936,6436,6536,6556,6560,
%T A192200 43424,55924,58424,58924,59024,59044,59048,140816,453316,515816,
%U A192200 528316,530816,531316,531416,531436,531440,2829844,4392344,4704844,4767344,4779844,4782344
%N A192200 Monotonic ordering of nonnegative differences 9^i-5^j, for 40>= i>=0, j>=0.
%t A192200 c = 9; d = 5; t[i_, j_] := c^i - d^j;
%t A192200 u = Table[t[i, j], {i, 0, 40}, {j, 0, i*Log[d, c]}];
%t A192200 v = Union[Flatten[u ]]
%Y A192200 Cf. A192199.
%K A192200 nonn
%O A192200 1,2
%A A192200 _Clark Kimberling_, Jun 25 2011