In extremal set theory, the Ahlswede–Khachatrian theorem generalizes the Erdős–Ko–Rado theorem to t-intersecting families. Given parameters n, k and t...

{\displaystyle n<(t+1)(r-t+1)} was determined by Ahlswede and Khachatrian, in their Ahlswede–Khachatrian theorem. The corresponding graph-theoretic formulation...

proof. Ahlswede, Rudolf; Khachatrian, Levon H. (1997), "Classical results on primitive and recent results on cross-primitive sequences: Theorem 1.11",...