%!PS
/R {144} def
/r {89} def
/h {55} def

% options
0.1 setlinewidth
2 setlinecap
2 setlinejoin

% set origin on center of page
/in {72 mul} def
8.5 in 2 div
11  in 2 div
translate

% Position x(t), y(t)
/x {
	/t exch def
	R r sub t cos mul
	t 1 R r div sub mul cos h mul
	add
	% Normalize
	144 mul R r sub h add div 
} def

/y {
	/t exch def
	R r sub t sin mul
	t 1 R r div sub mul sin h mul
	add
	% Normalize
	144 mul R r sub h add div 
} def

% a=mcd{r,R}
/a {r} def
/b {R} def
{
	b 0 ne exit if
	/x {a b mod} def
	/a {b} def
	/b {x} def
} loop

% Draw
0 x 0 y moveto
0 1 360 r r mul mul a div 
{
	dup x exch y lineto
} for

stroke
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