P. Erdős and Leon Alaoglu proved in [1] that for every $epsilon > 0$ the inequality $phi(sigma(n)) < epsilon cdot n$ holds for every $n in mathbb{N}$, except for a set of density $0$.
C. L. mentioned in [2] that as a consequence of the previous result one can ascertain that $displaystyle lim_{n to infty} frac{phi(sigma(n)) }{n} = 0.$
Does anybody know how it is that C. L. proceeded in order to arrive at such a conclusion?
Clearly enough, the fact that an inequality of the type $a_{n} < epsilon cdot n$ holds for every $epsilon > 0$ and a subset of $mathbb{N}$ of density $1$ does not imply, in general, that the sequence $displaystyle frac{a_{n}}{n}$ goes to $0$ as $n to infty$.
Hope you guys can shed some light on this inquiry of mine. Let me thank you in advance for your continued support.
References
[1] L. Alaoglu, P. Erdős: A conjecture in elementary number theory, Bull. Amer. Math. Soc. 50 (1944), 881-882.
[2] Mathematical Reflections, Solutions Dept, Issue #3, 2009, page 23.
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