JEWELL THEOREM FOR HIGHER DERIVATIONS ON C∗-ALGEBRAS Let A be an algebra. A sequence {d_n} of linear mappings on A is called a higher derivation if dn(ab) = sum_{j=0}^n d_j(a)d_{n−j}(b) for each a, b ∈ A and each nonnegative integer n. Jewell [Pacific J. Math. 68 (1977), 91-98], showed that a higher derivation from a Banach algebra onto a semisimple Banach algebra is continuous provided that ker(d_0) ⊆ ker(d_m), for all m>=1. In this paper, under a different approach using C∗-algebraic tools, we prove that each higher derivation {d_n} on a C∗-algebra A is automatically continuous, provided that it is normal, i. e. d_0 is the identity mapping on A.

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