A circle, 2n - 1 units in diameter, has been drawn symmetrically on a 2n × 2n chessboard, illustrated here for n = 3:
![908_1da8818e-791e-4af9-82fc-e2400cf7b3af.png](https://secure.tutorsglobe.com/CMSImages/908_1da8818e-791e-4af9-82fc-e2400cf7b3af.png)
a How many cells of the board contain a segment of the circle?
b Find a function f(n, k) such that exactly
cells of the board lie entirely within the circle.