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 A190554 #7 Jul 04 2017 21:19:07 %S A190554 7,12,24,36,41,53,65,70,82,94,106,111,123,135,140,152,164,176,181,193, %T A190554 205,210,222,234,239,246,251,263,275,280,292,304,309,321,333,345,350, %U A190554 362,374,379,391,403,408,415,420 %N A190554 Positions of 4 in A190549. %C A190554 See A190549. %H A190554 G. C. Greubel, <a href="/A190554/b190554.txt">Table of n, a(n) for n = 1..1000</a> %t A190554 r = Sqrt[2]; b = 4; c = 1; %t A190554 f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r]; %t A190554 t = Table[f[n], {n, 1, 200}] (* A190549 *) %t A190554 Flatten[Position[t, 0]] (* A190550 *) %t A190554 Flatten[Position[t, 1]] (* A190551 *) %t A190554 Flatten[Position[t, 2]] (* A190552 *) %t A190554 Flatten[Position[t, 3]] (* A190553 *) %t A190554 Flatten[Position[t, 4]] (* A190554 *) %Y A190554 Cf. A190549. %K A190554 nonn %O A190554 1,1 %A A190554 _Clark Kimberling_, May 12 2011