y = x2

-15-14-13-12-11-10-9-8-7-6-5-4-3-2-10123456789101112131415
225.00196.00169.00144.00121.00100.0081.0064.0049.0036.0025.0016.009.004.001.000.001.004.009.0016.0025.0036.0049.0064.0081.00100.00121.00144.00169.00196.00225.00