Two analogs of Pleijel's inequality

Abstract

Pleijel's inequality is an approximate inversion formula for the Stieltjes transform (or Cauchy integral) of a distribution function on positive semi-axis. It implies a Tauberian theorem due to Malliavin. The proposed analogs of Pleijel's inequality deal with (1) approximate recovery of the Riesz means of the distribution function from its Stieltjes transform, and (2) approximate recovery of the distribution function with power growth for which the ordinary Stieltjes transform does not exist. In the latter case, a power of the Cauchy (or Stieltjes) kernel is used to define the "generalized Stieltjes transform". A previously unpublished theorem stated in Appendix pertains to combination of the two situations (input: generalized Stieltjes transform; output: Riesz means).