# Rate of large composite numbers, which are strong probable prime to the bases $2,3$ and $5$

Here

http://primes.utm.edu/glossary/xpage/StrongPRP.html

is the definition and some useful informations about strong probable primes.

For higher numbers, lets say near $10^{50}$, strong probable primes to bases $2,3$ and $5$ should be very rare.

What is the approximate rate of composite numbers near $n$, which are strong probable primes to the bases $2,3$ and $5$ ?

Intuitively, the rate should decrease if the numbers get bigger, but I am not sure, if this is the case. I only know that there are inifite many numbers with the desired property.

This site

shows, that a big random number which is probable prime to a smaller random base, is prime with a very high probability. But here, the base is not fixed, so I do not know if this helps for my question.