%I #8 Oct 04 2022 21:21:52
%S 1,1,1,1,2,1,2,2,2,4,4,8,4,4,4,8,8,8,8,16,8,16,16,16,32,16,16,16,32,
%T 32,32,32,32,32,32,64,64,128,64,64,64,64,64,64,64,128,128,128,128,128,
%U 128,256,128,128,128,256,256,256,256,512,256,256,256,256,256,256,512
%N Algebraic degree of cos(2*Pi/n) for constructible n-gons (A003401).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TrigonometryAngles.html">Trigonometry Angles</a>
%Y Cf. A003401, A023022, A113402.
%K nonn,easy,nice
%O 1,5
%A _Eric W. Weisstein_, Oct 28 2005