Math 21a Fall 2000 The Robert Yeh Curve Back
 r[t_]:={{4*t*(300/(t+1)^7+1) Sin[(200/(t+1)^3+1)*8t],
               4*t*(300/(t+1)^7+1) Cos[(200/(t+1)^3+1)*8t],
               (7/Sqrt[t+1]+1)^2(5-2*t Sin[t/10]^2 Cos[t/9]^2)}