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arXiv · 2407.01043

A generalized version of Holmstedt's formula for the K-functional

Irshaad Ahmed·Alberto Fiorenza·Amiran Gogatishvili
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Abstract

Let $(A_0, A_1)$ be a compatible couple of quasi-normed spaces, and let $Φ_0$ and $Φ_1$ be two general parameters of $K$-interpolation method. We compute $K$-functional for the couple $((A_0,A_1)_{Φ_0}, (A_0, A_1)_{Φ_1})$ in terms of $K$-functional for the couple $(A_0, A_1)$.

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Irshaad Ahmed, Alberto Fiorenza, Amiran Gogatishvili. 2024-07-01. A generalized version of Holmstedt's formula for the K-functional. https://arxiv.org/abs/2407.01043

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