de Finetti Lattices and Magog Triangles

Andrew Beveridge, Ian Calaway, Kristin Heysse

The order ideal $B_{n,2}$ of the Boolean lattice $B_n$ consists of all subsets of size at most $2$. Let $F_{n,2}$ denote the poset refinement of $B_{n,2}$ induced by the rules: $i…