Iteration No.     32
initial parameters' values:
a1 = 206.060000  a2 = -41.074000  a3 = 2.047000
fitted parameters' values:
a1 = 206.0493 ± 1.366452e-05
a2 = -41.07435 ± 3.043494e-06
a3 = 2.047005 ± 3.378892e-07
cov(a1,a2) = -9.085986e-11
cov(a1,a3) = 5.981925e-12
cov(a2,a3) = -8.213953e-13
chi^2 = 0.57252
ndf = 4
chi^2_reduced = 0.14313
p probability = 0.96607