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On the tree structure of natural numbers. II
Each natural number can be associated with some tree graph. Namely,
a natural number $n$ can be factored as
$$ n = p_1^{\alpha_1}\cdots p_k^{\alpha_k},$$
where
$p_i$ are distinct prime numbers. Since
$\alpha_i$ are naturals, they can be factored in such a manner as well.
This process may be continued, building the ''factorization tree'' until all
the top numbers are $1$. Let $H(n)$ be the height of the tree corresponding to the number $n$, and let the symbol $\uparrow\uparrow$ denotes tetration. In this paper, we derive the asymptotic
formulas for the sums
$$\mathcal{M}(x) = \sum_{p\leqslant x} H(p-1),\ \ \mathcal{H}(x) = \sum_{n\leqslant x}2\uparrow\uparrow H(n),$$
and
$$\mathcal{L}(x) = \sum_{n\leqslant x}\dfrac{2\uparrow\uparrow H(n)}{2\uparrow\uparrow H(n+1)},$$
where the summation in the first sum is taken over primes.