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The equality problem in the class of conjugate means

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Abstract

Let \({I\subset\mathbb{R}}\) be a nonempty open interval and let \({L:I^2\to I}\) be a fixed strict mean. A function \({M:I^2\to I}\) is said to be an L-conjugate mean on I if there exist \({p,q\in{]}0,1]}\) and a strictly monotone and continuous function φ such that

$$M(x,y):=\varphi^{-1}(p\varphi(x)+q\varphi(y)+(1-p-q)\varphi(L(x,y)))=:L_\varphi^{(p,q)}(x,y),$$

for all \({x,y\in I}\) . Here L(x, y) is a fixed quasi-arithmetic mean. We will solve the equality problem in this class of means.

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Correspondence to Judita Dascăl.

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This research has been supported by the Hungarian Scientific Research Fund (OTKA) Grant NK 81402 (first and second author) and OTKA “Mobility” call HUMAN-MB08A-84581 (first author).

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Burai, P., Dascăl, J. The equality problem in the class of conjugate means. Aequat. Math. 84, 77–90 (2012). https://doi.org/10.1007/s00010-011-0113-y

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  • DOI: https://doi.org/10.1007/s00010-011-0113-y

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