On orbit equivalent permutation groups
The author gives a proof, independent of the classification of the finite simple groups, of a theorem of A. Wagner that shows there are but seven exceptions to the statement: If two primitive groups acting on the same set X have the same orbits on \(2^ X\) and one is contained in the other, then they are equal. The author states that Siemons and Wagner have independently given such a proof.
scientific article; zbMATH DE number 3867548