Mathieu group

In the area of modern algebra known as group theory, the Mathieu groups are the five sporadic simple groups M₁₁, M₁₂, M₂₂, M₂₃ and M₂₄ introduced by Mathieu (1861, 1873). They are multiply transitive permutation groups on 11, 12, 22, 23 or 24 objects. They were the first sporadic groups to be discovered.