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Legacy Documentation

The Mathematical Explorer^TM (2001)

This is documentation for an obsolete product.

PrimePi PrimePi[ x ] gives the number of primes less than or equal to x. The argument of PrimePi can be any positive real number. PrimePi[1] gives 0. See The Mathematica Book on the web:Section 3.2.4. Implementation Notes on the web: see Section A.9.4. See also: Prime, Zeta. Further Examples