English

An Improved Lower Bound for $S(7)$ and Some Interesting Templates

Combinatorics 2021-07-09 v1

Abstract

In this simple paper, we exhibit a Schur partition giving rise to a triangle-free linear colouring of K1697K_{1697} in 7 colours. Thus we show that the Schur number S(7)1696S(7) \ge 1696 and the multicolour Ramsey number R7(3)1698R_{7}(3) \ge 1698. We also demonstrate a specific partition of the closed integer interval [1,376][1, 376] which, through repeated use of a specific construction, allows us to conclude that S(k+5)376.S(k)+160S(k+5) \ge 376.S(k)+160 for any positive integer kk. The existence of this partition, with its specific properties, implies that limrRr(3)1/r>3.273\lim_{\substack{r \rightarrow \infty}} R{_r}(3)^{1/r} > 3.273.

Keywords

Cite

@article{arxiv.2107.03560,
  title  = {An Improved Lower Bound for $S(7)$ and Some Interesting Templates},
  author = {Fred Rowley},
  journal= {arXiv preprint arXiv:2107.03560},
  year   = {2021}
}

Comments

4 pages & ancillary files of exhibits

R2 v1 2026-06-24T03:59:07.272Z