A Separation Between Run-Length SLPs and LZ77

@article{Bille2017ASB,
  title={A Separation Between Run-Length SLPs and LZ77},
  author={Philip Bille and Travis Gagie and Inge Li G\ortz and Nicola Prezza},
  journal={CoRR},
  year={2017},
  volume={abs/1711.07270}
}
In this paper we give an infinite family of strings for which the length of the Lempel-Ziv’77 parse is a factor Ω(log n/ log log n) smaller than the smallest run-length grammar.