Euc20205/Sub-Problem 1

Revision as of 03:24, 31 March 2023 by Tonyliu (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

(a) For each positive real number x, define $f(x)$ to be the number of prime numbers $p$ that satisfy $x \le p \le x + 10$. What is the value of $f(f(20))$?