Apparent indiscrepancy in the average value of phi function

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The discussion centers on the average value of the Totient function, denoted as ##\phi(n)##. It references the assertion from "Introduction to the Theory of Numbers" that the average order of ##\phi(n)## is ##\frac{6\cdot n}{\pi^2}##. The contributor questions this conclusion, suggesting that the average value should be ##\frac{3\cdot n}{\pi^2}## based on their interpretation of the asymptotic behavior of the summation of the Totient function. The mathematical definitions provided clarify the relationship between the average order of arithmetic functions and their respective asymptotic behaviors.

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So, while solving a problem a friend came up with involving the Totient function, I ended up doing a bit of research into the average asymptotics of the function. On page 268 of Introduction to the Theory of Numbers, it's mentioned that "The average of order of ##\phi\left(n\right)## is ##\frac{6\cdot n}{\pi^2}##. More precisely, ##\Phi\left(n\right)=\phi\left(1\right)+\ldots+\phi\left(n\right)=\frac{3\cdot n^2}{\pi^2}+O\left(n\cdot\log\left(n\right)\right)##."

My question is, wouldn't this mean ##\frac{\phi\left(1\right)+\ldots+\phi\left(n\right)}{n}\approx\frac{3\cdot n}{\pi^2}##, so the average value of the phi function up to n would be approximately ##\frac{3\cdot n}{\pi^2}## and not, as previously stated, ##\frac{6\cdot n}{\pi^2}##?
 
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Recall that an arithmetic function ##f## is said to be of the average order of a function ##g## if
$$f(1)+f(2) + \cdots + f(n) \sim g(1) + g(2) + \cdots + g(n)$$
Let ##f(n)=\phi(n)## and ##g(n)=\frac{6n}{\pi^2}##.
Then ##\phi(n)## has average order ##\frac{6n}{\pi^2}## means that
$$\phi(1)+\phi(2)+\cdots+\phi(n)\sim\frac{6}{\pi^2}(1+2+\cdots+n)$$
and ##1+2+\cdots+n\sim\frac{1}{2}n^2##.
 
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