cucu62
 k =0  x = 0.250000   val =0.550050  err=0.000719  val pos=0.547307  err pos=0.001016  val neg=0.552808  err neg=0.001017
 k =1  x = 0.750000   val =0.534048  err=0.001004  val pos=0.534656  err pos=0.001396  val neg=0.533396  err neg=0.001445
 k =2  x = 1.250000   val =0.534038  err=0.002126  val pos=0.536545  err pos=0.002885  val neg=0.531066  err neg=0.003143
 k =3  x = 1.750000   val =0.523230  err=0.004425  val pos=0.524194  err pos=0.005993  val neg=0.522077  err neg=0.006560
 k =4  x = 2.250000   val =0.524908  err=0.009131  val pos=0.527761  err pos=0.012198  val neg=0.521277  err neg=0.013770
 k =5  x = 2.750000   val =0.512887  err=0.017943  val pos=0.513978  err pos=0.023178  val neg=0.511254  err neg=0.028345
 k =6  x = 3.250000   val =0.511111  err=0.033325  val pos=0.511628  err pos=0.044011  val neg=0.510417  err neg=0.051020
 k =7  x = 3.750000   val =0.539683  err=0.062795  val pos=0.520833  err pos=0.072106  val neg=0.600000  err neg=0.126491


cucu200
 k =0  x = 0.250000   val =0.510777  err=0.000777  val pos=0.508477  err pos=0.001098  val neg=0.513082  err neg=0.001099
 k =1  x = 0.750000   val =0.482867  err=0.001033  val pos=0.481027  err pos=0.001450  val neg=0.484763  err neg=0.001473
 k =2  x = 1.250000   val =0.477075  err=0.002047  val pos=0.471494  err pos=0.002839  val neg=0.483093  err neg=0.002952
 k =3  x = 1.750000   val =0.472967  err=0.003868  val pos=0.470358  err pos=0.005350  val neg=0.475820  err neg=0.005597
 k =4  x = 2.250000   val =0.457065  err=0.007218  val pos=0.452572  err pos=0.009979  val neg=0.461978  err neg=0.010452
 k =5  x = 2.750000   val =0.438499  err=0.013081  val pos=0.399215  err pos=0.017718  val neg=0.482963  err neg=0.019234
 k =6  x = 3.250000   val =0.444898  err=0.022450  val pos=0.423358  err pos=0.029849  val neg=0.472222  err neg=0.033968
 k =7  x = 3.750000   val =0.386076  err=0.038732  val pos=0.361111  err pos=0.056607  val neg=0.406977  err neg=0.052975