Abstract We establish off-diagonal extrapolation on mixed variable Lebesgue spaces. As its applications, we obtain the boundedness for strong fractional maximal operators. The vector-valued analogies are also considered. Additionally, the Littlewood–Paley characterization for mixed variable Lebesgue spaces is also established with the help of weighted norm inequalities and extrapolation.

中文翻译：

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混合变量 Lebesgue 空间的非对角外推及其在强分数极大算子上的应用

摘要 我们建立了混合变量 Lebesgue 空间的非对角外推。作为它的应用，我们获得了强分数极大算子的有界性。还考虑了向量值类比。此外，还借助加权范数不等式和外推法建立了混合变量 Lebesgue 空间的 Littlewood-Paley 表征。