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Is there a general method to arrange $n^n$, $(n-1)^{(n-1)}$, $(n+1)^{(n+1)}$, $(n-1)^{(n+1)}$, $(n+1)^{(n-1)}$ in ascending order?

I am interested in a general method which works for all real values of n.

Highly original and intuitive methods which may work for specific cases of n also appreciated.

I would also like to understand some beautiful and thought provoking methods(such as proof without words)

Eventually,

My last question is whether we can arrange

$n^n$, $(n-k)^{(n-k)}$, $(n+k)^{(n+k)}$, $(n-k)^{(n+k)}$, $(n+k)^{(n-k)}$ in ascending order.

Where $k$ is a arbitrary positive constant.

Caution : Consider only those values for the above expressions are defined and real.

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    General Approaches to consider.2017-02-25
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    1. Induction 2. Calculus(maybe) 3.Graphical 4. Using some identity?2017-02-25
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    For many real values of $n$, the indicated quantities are not defined. Perhaps you'd be happy with, e.g., $n > 1$?2017-02-25
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    @Travis Yes I edited the question to make it more clear. Thanks for pointing it out.2017-02-25
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    for what stands $k$ here?2017-02-25
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    @Dr.SonnhardGraubner Thanks, I defined $k$ as you had asked me to do.2017-02-25

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(Note that the question moved on while I was thinking and typing... I leave this here anyway for interest)

Provided all the quantities are greater than $e$, you have that for $a>b, a^be$, it is clear that $a^bb$ if both are in this range.

The remaining uncertainty is ordering $n^n$ and $(n-k)^{n+k}$ (and I read $k$ as a small offset on $n$, rather than an unconstrained value). $k$ has to be a significant proportion of $n$, in general, to undermine $(n-k)^{n+k}>n^n$. For example (in the integers) for $n=23$ you only need $k<17$ to keep $(n-k)^{n+k}>n^n$ .

So least for $n\ge5$, the initial asked ordering is $$(n-1)^{(n-1)}<(n+1)^{(n-1)}


($5$ is the minimum value in the integers for this ordering, but the actual crossover in the reals is extremely close to $n=\pi+1$, above which point $n^n<(n-1)^{(n+1)}$ is true. This threshold value is from (spreadsheet) calculation, not any theoretical assessment).

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    I actually did not get what you are trying to say.2017-02-25
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    Can you edit your answer especially the last part to explain it a little more clearly?2017-02-25
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    Ah, you're right, of course!2017-02-25
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    @Travis Can you clarify? What is right?2017-02-26
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    @PrashantGokhale I was responding to Joffan.2017-02-26
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    @Travis Oh Sorry!2017-02-26