Bounding extremal functions of forbidden $0-1$ matrices using $(r,s)$-formations

Jesse Geneson, Meghal Gupta

First, we prove tight bounds of $n{2}^{\frac{1}{(t-2)!}\alpha (n{)}^{t-2}\pm O(\alpha (n{)}^{t-3})}$ on the extremal function of the forbidden pair of ordered sequences $(123\dots k{)}^t$ and $(…