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 A190241 #9 Dec 27 2017 01:37:24
%S A190241 1,2,3,4,6,7,8,9,11,12,13,14,16,17,18,19,22,23,24,27,28,32,33,37,38,
%T A190241 43,48,55,56,57,59,60,61,62,64,65,66,67,69,70,71,72,74,75,76,80,81,85,
%U A190241 86,90,91,95,96,101,109,110,111,112,113,114,115,117,118,119,120,122,123,124,125,127,128,129,132,133,134,138,139,143,144,148,149,164
%N A190241 Positions of 1 in A190239; complement of A190240.
%H A190241 G. C. Greubel, <a href="/A190241/b190241.txt">Table of n, a(n) for n = 1..5500</a>
%t A190241 u = Exp[Pi/2]; v = 1/u;
%t A190241 f[n_] := Floor[n*u + n*v] - Floor[n*u] - Floor[n*v]
%t A190241 t = Table[f[n], {n, 1, 120}] (*A190239*)
%t A190241 Flatten[Position[t, 0]] (*A190240*)
%t A190241 Flatten[Position[t, 1]] (*A190241*)
%Y A190241 Cf. A190239, A190240.
%K A190241 nonn
%O A190241 1,2
%A A190241 _Clark Kimberling_, May 06 2011