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%I #31 Oct 27 2019 12:56:11
%S 1,3,7,5,11,7,5,9,19,11,23,13,9,15,31,17,35,19,13,21,43,23,47,25,17,
%T 27,55,29,59,31,21,33,67,35,71,37,25,39,79,41,83,43,29,45,91,47,95,49,
%U 33,51,103,53,107,55,37,57,115,59,119,61,41,63,127,65,131,67
%N Numerators associated with A328184.
%C Geometric Interpretation: Given n-sided regular polygon "rolling" on a flat surface with constant angular velocity, a(n) is the numerator of the ratio:
%C [("time" taken for any one vertex to move from highest point to lowest point) / ("time" taken for polygon to finish one complete turn)] := b(n).
%C Lim_{n->infinity} b(n) = 1/2 (can be easily proven).
%H Luca Alexander, <a href="/A328185/a328185.txt">about 100000 terms</a>
%F a(n) = numerator((n - 1) / (2*n)) for even n; a(n) = numerator((2*n - 3) / (4*n)) for odd n.
%e For n = 3, a(3) = numerator of ((2*3-3)/4*n) = numerator of (3/12) = numerator of (1/4) = 1.
%t Array[Numerator[(2 (# - 1) - Mod[#, 2])/(4 #)] &, 66, 3] (* _Michael De Vlieger_, Oct 06 2019 *)
%o (PARI) a(n) = {numerator((2*(n-1) - n%2)/(4*n))} \\ _Andrew Howroyd_, Oct 06 2019
%Y Cf. A328184 (denominators).
%K frac,nonn
%O 3,2
%A _Luca Alexander_, Oct 06 2019
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