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 A192120 #13 Nov 16 2021 13:34:05
%S A192120 0,1,3,7,8,15,24,31,56,63,64,120,127,192,248,255,448,504,511,512,960,
%T A192120 1016,1023,1536,1984,2040,2047,3584,4032,4088,4095,4096,7680,8128,
%U A192120 8184,8191,12288,15872,16320,16376,16383,28672,32256,32704,32760,32767,32768
%N A192120 Monotonic ordering of nonnegative differences 2^i - 8^j, for 40 >=i >= 0, j >= 0.
%H A192120 Nathaniel Johnston, <a href="/A192120/b192120.txt">Table of n, a(n) for n = 1..288</a> [truncated to 2^40-1 by _Georg Fischer_, Nov 16 2021]
%p A192120 A192120:={}: for i from 0 to 15 do for j from 0 to floor(i/3) do A192120 := A192120 union {2^i-8^j}: od: od: op(A192120); # _Nathaniel Johnston_, Jun 23 2011
%t A192120 c = 2; d = 8; t[i_, j_] := c^i - d^j;
%t A192120 u = Table[t[i, j], {i, 0, 40}, {j, 0, i*Log[d, c]}];
%t A192120 v = Union[Flatten[u ]]
%Y A192120 Cf. A192110, A192121.
%K A192120 nonn,easy,fini
%O A192120 1,3
%A A192120 _Clark Kimberling_, Jun 23 2011