On families of subsets with a forbidden subposet

Jerrold R. Griggs, Linyuan Lu

Let $\F\subset 2^{[n]}$ be a family of subsets of $\{1,2,...,n\}$. For any poset $H$, we say $\F$ is $H$-free if $\F$ does not contain any subposet isomorphic to $H$. Katona and o…