$1$-cross intersecting set pair systems are small

Dylan King, Van Magnan, Cory Palmer

A set pair system $\{(A_i,B_i){\}}_{i=1}^m$ is $1$-cross intersecting if $|A_i\cap B_i|=0$ for all $i$ and $|A_i\cap B_j|=1$ whenever $i\ne j$. Let $m(a,b,1)$ denote the maximu…