Article
Keywords:
Banach algebra; weakly amenable; Arens regular; $n$-weakly amenable
Summary:
In this paper we extend the notion of $n$-weak amenability of a Banach algebra $\mathcal A$ when $n\in \mathbb{N}$. Technical calculations show that when $\mathcal A$ is Arens regular or an ideal in $\mathcal A^{**}$, then $\mathcal A^*$ is an $\mathcal A^{(2n)}$-module and this idea leads to a number of interesting results on Banach algebras. We then extend the concept of $n$-weak amenability to $n \in \mathbb{Z}$.
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