A numerical point of view at the Gurov-Reshetnyak inequality on the real   line
  A "norm" of power function in the Gurov-Reshetnyak class on the real line is computed. Moreover, a lower bound for the norm of the operator of even extension from the semi-axis to the whole real line in the Gurov-Reshetnyak class is obtained from numerical experiments. 
Victor D. Didenko, Anatolii A. Korenovskyi, Nor Jaidi Tuah
math.CA