Prime-Counting Function/Examples/16

Definition

The value of the prime-counting ($\pi$) function for $16$ is determined as follows.

The prime numbers less than $16$ are:

$2, 3, 5, 7, 11, 13$

Hence:

$\map \pi {16} = 6$

Sources

• 2008: David Joyner: Adventures in Group Theory (2nd ed.) ... (previous) ... (next): Chapter $2$: 'And you do addition?': $\S 2.1$: Functions: Ponderable $2.1.1$