Extensions of democracy-like properties for sequences with gaps

Abstract: In \cite{O2015}, T. Oikhberg introduced and studied variants of the greedy and weak greedy algorithms for sequences with gaps. In this paper, we extend some of the notions that appear naturally in connection with these algorithms to the context of sequences with gaps. In particular, we will consider sequences of natural numbers for which the inequality $n_{k+1}\le \C n_{k}$ or $n_{k+1}\le \C+n_k$ holds for a positive constant $\C$ and all $k$, and find conditions under which the extended notions are equivalent their regular counterparts.