Avoiding two consecutive blocks of same size and same sum over $\mathbb{Z}^2$
Combinatorics
2016-10-03 v2 Discrete Mathematics
Formal Languages and Automata Theory
Abstract
A long standing question asks whether is uniformly 2-repetitive [Justin 1972, Pirillo and Varricchio, 1994], that is, whether there is an infinite sequence over a finite subset of avoiding two consecutive blocks of same size and same sum or not. Cassaigne \emph{et al.} [2014] showed that is not uniformly 3-repetitive. We show that is not uniformly 2-repetitive. Moreover, this problem is related to a question from M\"akel\"a in combinatorics on words and we answer to a weak version of it.
Cite
@article{arxiv.1511.05875,
title = {Avoiding two consecutive blocks of same size and same sum over $\mathbb{Z}^2$},
author = {Michaël Rao and Matthieu Rosenfeld},
journal= {arXiv preprint arXiv:1511.05875},
year = {2016}
}