# Sharp weak type estimates for weights in the class $A_{p_1, p_2}$

### Alexander Reznikov

Vanderbilt University, Nashville, USA

## Abstract

We get sharp estimates for the distribution function of nonnegative weights that satisfy the so-called $A_{p_1, p_2}$ condition. For particular choices of parameters $p_1$, $p_2$ this condition becomes an $A_p$-condition or reverse Hölder condition. We also get maximizers for these sharp estimates. We use the Bellman technique and try to carefully present and motivate our tactics. As an illustration of how these results can be used, we deduce the following result: if a weight $w$ is in $A_2$ then it self-improves to a weight that satisfies a reverse Hölder condition.

## Cite this article

Alexander Reznikov, Sharp weak type estimates for weights in the class $A_{p_1, p_2}$. Rev. Mat. Iberoam. 29 (2013), no. 2, pp. 433–478

DOI 10.4171/RMI/726