NGC104 (47 Tuc) 
 6 iterations.
Chebyshev coeffients a(0)T_0(u)+a(1)T_1(u)+..., where u is log (r/arcsec) mapped to [-1,1]
 a(0)=    19.472 +-  0.112
 a(1)=     6.036 +-  0.177
 a(2)=     1.130 +-  0.172
 a(3)=     0.314 +-  0.141
 a(4)=     0.166 +-  0.138
Power-of-x coeffients a(0)+a(1)x+a(2)x^2+..., where x=1+(r/r_c)^2, r_c= 1.42
 a(0)=     4.6828
 a(1)=     0.7515
 a(2)=     1.0310
 a(3)=    -0.3647
 a(4)=     0.0534
log r(arcsec)   mu_V    mu_V(fitted)  residual   weight  data set