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This post is cross posted from Mathematics Stack Exchange, due that there was a mistake from my part (see the excellent partial answer and my thread of edits of my question on MSE) this post on MathOverflow is slightly different of On variations of a claim due to Kaneko in terms of Lehmer means asked 30 days ago (May 13) as the question with identificator 3672588 of Mathematics Stack Exchange.

For a tuple of positive real numbers $\mathbb{x}=(x_1,x_2,\ldots,x_n)$ we denote its corresponding Lehmer mean as $L_q(\mathbb{x})$, where $-1\lt q\lt 0$, I know the definition of these means from the corresponding Wikipedia with title Lehmer mean..

Also we denote the sum of divisors function as $\sigma(n)=\sum_{1\leq d\mid n}d$ for integers $n\geq 1$.

The idea of the post was to combine this definition of Lehmer mean with an equivalent formulation of the Riemann hypothesis, I refer the last paragraph of [1] (Kaneko's claim for a suitable choice of the integer $n_0$ from which the inequality in Kaneko's claim is true $\forall n\geq n_0$).

From here, my belief that there should be an integer $n_0>1$ such that $\forall n\geq n_0$ the following inequality holds $$\sigma(n)<\exp\left(\frac{n}{L_q(1,\ldots,n)}\right)\log\left(\frac{n}{L_q(1,\ldots,n)}\right)\tag{1}$$ specifically for real numbers $-1\lt q\lt 0$.

Fact. We've from the theory of Lehmer mean that we recover the inequality of Kaneko as $q$ tends to $0^{-}$.

Sketch of proof. From the section of Properties and Special cases of the linked Wikipedia, and the continuity of a product of continuous functions (our exponential and logarithm).$\square$

Question. I would like to know what work can be done to prove an inequality of the form $(1)$ for a specific value of $-1<q<0$, the least/smallest value of $|q|$ for which it is possible to prove that your inequality is true (I mean very close to $0$), and that holds $\forall n\geq n_0$ for a suitable choice of $n_0>1$ for your corresponding choice of a specific value of $-1<q<0$.

Many thanks.

I emphasize that I'm asking what work can be done to prove an example for one of those inequalities $(1)$ for a very small quantity $|q|>0$ with $-1<q<0$ and that is true, our inequality, as a relaxation of Kaneko's claim for a segment of integers $n_0<n$. Feel free to add your feedback about if this type of inequalities (my interpretation of a relaxation or variation of Kaneko's claim) and combinations can be potentially interesting.

References:

[1] Jeffrey C. Lagarias, An Elementary Problem Equivalent to the Riemann Hypothesis, The American Mathematical Monthly, 109, No. 6 (2002), pp. 534-543.

[2] P. S. Bullen, Handbook of Means and Their Inequalities, Springer, (1987).

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  • $\begingroup$ Feel free to add your feedback about the question, what I tried to evoke with my question (once I have noticed from the excellent partial answer of MSE the possible flaws in my statements) is try to prove an inequality $(1)$ similar than Kaneko's claim for suitable values of $-1<q<0$ and $n_0$, thus in my interpretation a relaxation, in some way, of the Riemann hypothesis. Many thanks for the attention and patience of users, and good day. $\endgroup$
    – user142929
    Commented Jun 12, 2020 at 9:52
  • $\begingroup$ As aside comment (or companion/comparison reference for this MO post) I've also edited on Mathematics Stack Exchange the post with title Around a weak form of the Riemann hypothesis inspired in the relationship between the Stolarsky means and the logarithmic mean, that is the MSE question with identificator 3626466 (asked Apr 15) without an available answer (please if can with your MSE acount add your feedback in comments on the site MSE about the quesiton). $\endgroup$
    – user142929
    Commented Jun 12, 2020 at 10:48

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