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arXiv · 1911.01667

Regularity of bounded tri-linear maps and the fourth adjiont of a tri-derivation

Abotaleb Sheikhali·Ali Ebadian·Kazem Haghnejad Azar
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Abstract

In this Article, we give a simple criterion for the regularity of a tri-linear mapping. We provide if $f:X\times Y\times Z\longrightarrow W $ is a bounded tri-linear mapping and $h:W\longrightarrow S$ is a bounded linear mapping, then $f$ is regular if and only if $hof$ is regular. We also shall give some necessary and sufficient conditions such that the fourth adjoint $D^{****}$ of a tri-derivation $D$ is again tri-derivation.

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Abotaleb Sheikhali, Ali Ebadian, Kazem Haghnejad Azar. 2019-11-05. Regularity of bounded tri-linear maps and the fourth adjiont of a tri-derivation. https://arxiv.org/abs/1911.01667

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