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 A190565 #8 Jul 04 2017 21:19:24 %S A190565 2,7,9,14,19,21,26,31,36,38,43,48,50,55,60,65,67,72,77,79,84,89,91,94, %T A190565 96,101,106,108,113,118,120,125,130,135,137,142,147,149,154,159,164, %U A190565 166,171,176,178,183,188,190,195,200,205,207,212,217,219,224,229,234,236,241,246,248,253,258,260,263,265,270,275,277,282,287 %N A190565 Positions of 3 in A190561. %C A190565 See A190561. %H A190565 G. C. Greubel, <a href="/A190565/b190565.txt">Table of n, a(n) for n = 1..1000</a> %t A190565 r = Sqrt[2]; b = 4; c = 3; %t A190565 f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r]; %t A190565 t = Table[f[n], {n, 1, 200}] (* A190561 *) %t A190565 Flatten[Position[t, 0]] (* A190562 *) %t A190565 Flatten[Position[t, 1]] (* A190563 *) %t A190565 Flatten[Position[t, 2]] (* A190564 *) %t A190565 Flatten[Position[t, 3]] (* A190565 *) %t A190565 Flatten[Position[t, 4]] (* A190566 *) %Y A190565 Cf. A190561. %K A190565 nonn %O A190565 1,1 %A A190565 _Clark Kimberling_, May 12 2011