<image>As shown in the figure, a segment of the parabola \( C_1 \) corresponds to the function \( y = -x(x-4) \) for \( 0 \leq x \leq 4 \), and it intersects the x-axis at points \( O \) and \( A_1 \). Rotating \( C_1 \) 180° around point \( A_1 \) results in \( C_2 \), which intersects the x-axis at point \( A_2 \). Rotating \( C_2 \) 180° around point \( A_2 \) results in \( C_3 \), which intersects the x-axis at point \( A_3 \). Continuing this process until \( C_{16} \) is obtained, if point \( P(61, n) \) lies on the 16th segment of the parabola \( C_{16} \), then \( n = ____ \).