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 A192153 #6 Oct 21 2019 14:49:59
%S A192153 0,2,8,20,26,32,74,80,194,236,242,386,680,722,728,1844,2138,2180,2186,
%T A192153 2876,4160,6218,6512,6554,6560,17282,19340,19634,19676,19682,42242,
%U A192153 56648,58706,59000,59042,59048,59498,160340,174746,176804,177098,177140,177146
%N A192153 Monotonic ordering of nonnegative differences 3^i-7^j, for 40>= i>=0, j>=0.
%t A192153 c = 3; d = 7; t[i_, j_] := c^i - d^j;
%t A192153 u = Table[t[i, j], {i, 0, 40}, {j, 0, i*Log[d, c]}];
%t A192153 v = Union[Flatten[u ]]
%Y A192153 Cf. A192154.
%K A192153 nonn
%O A192153 1,2
%A A192153 _Clark Kimberling_, Jun 24 2011