{
gROOT->Reset();
form1 = new TFormula("form1","[0]+[1]*TMath::Log(x)+[2]*TMath::Log(x)*TMath::Log(x)");
TF1 *fun1 = new TF1("fun1","form1",20,55);
fun1->SetParameters(0.122,0.234,-0.018);
fun1->Draw();
}