Let G be a Mathieu simple group, s is an element of G, O-s the conjugacy class of s and rho an irreducible representation of the centralizer of s. We prove that either the Nichols algebra B(O-s, rho) is infinite-dimensional or the braiding of the Yetter-Drinfeld module M(O-s, rho) is negative. We also show that if G = M-22 or M-24, then the group algebra of G is the only (up to isomorphisms) finite-dimensional complex pointed Hopf algebra with group-likes isomorphic to G.
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