Is there any sort of standard notation for the value represented by $f(n) = \frac{\Lambda(n)}{\log n}$, where $\Lambda(n)$ is the Mangoldt function? So essentially a function that is $\frac {1}{a}$ when $n$ is equal to some prime $p$ to the power of $a$, and 0 otherwise.
And while on the subject, is there any consensus about notation for its summatory function, which is also equal to $\pi(n) + \frac{1}{2}\pi(n^\frac{1}{2})+ \frac{1}{3}\pi(n^\frac{1}{3})+\cdots$, where $\pi(n)$ is the prime counting function? Riemann called it $f(n)$, I believe, Edwards calls it $J(n)$, Crandall and Pomerance seem to refer to it as $\pi^*(n)$, and I've found several other references that refer to it as $\Pi(n)$. I feel like I've seen $\Pi(n)$ more often, but not enough to feel confident...