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 A176360 #6 Apr 09 2020 19:08:06
%S A176360 1,2,2,3,4,4,1,2,2,3,4,4,1,1,2,3,3,4,1,1,2,3,3,4,4,1,2,2,3,4,4,1,2,2,
%T A176360 3,3,4,1,1,2,3,3,4,1,1,2,2,3,4,4,1,2,2,3,4,4,1,1,2,3,3,4,1,1,2,3,3,4,
%U A176360 4,1,2,2,3,4,4,1,2,2,3,3,4,1,1,2,3,3,4,1,1,2,2,3,4,4,1,2,2,3,4,4,1,1,2,3,3
%N A176360 a(n) = quadrant of unit circle corresponding to n radians.
%C A176360 Radians are the natural measure of angle. Quadrants (1 through 4) determine the signs of (x,y); of (cos x, sin x); and are ubiquitous.
%C A176360 Thereby it is "interesting" to consider which quadrant contains successively larger integer radian measure.
%F A176360 a(n) = 1 + {floor [2*n/Pi] modulo(4)}. - _Adam Helman_, Apr 20 2010
%e A176360 a(11) is very nearly 7 quadrants as Pi is nearly exactly 22/7.
%e A176360 Indeed, 11 radians lies just 4.4 milliradian (0.25 degree) within the 4th quadrant.
%t A176360 Table[Mod[1+Floor[(2n)/Pi],4],{n,120}]/.(0->4) (* _Harvey P. Dale_, Apr 09 2020 *)
%o A176360 From _Adam Helman_, Apr 20 2010: (Start)
%o A176360 (Other) # a(n) = 1 + {floor [2*n/pi] modulo(4)}
%o A176360 # Ruby code by Andy Martin
%o A176360 # Overkill here, 4 places properly gives first 200 terms.
%o A176360 t = 2000000000000000000000000000000000000000000000000000000000000000000
%o A176360 pi = 3141592653589793238462643383279502884197169399375105820974944592307
%o A176360 (1..200).each{ |n| print "#{1 + ((n*t)/pi)%4},"}
%o A176360 print "\b \n"
%o A176360 (End)
%K A176360 nonn,easy
%O A176360 1,2
%A A176360 _Adam Helman_, Apr 15 2010, Apr 20 2010