In mathematics, the Feller–Tornier constant CFT is the density of the set of all positive integers that have an even number of distinct prime factors raised to a power larger than one (ignoring any prime factors which appear only to the first power). It is named after William Feller (1906–1970) and Erhard Tornier (1894–1982)

Omega function

The Big Omega function is given by

The Iverson bracket is

With these notations, we have

Prime zeta function

The prime zeta function P is give by

The Feller–Tornier constant satisfies

See also Riemann zeta function L-function Euler product Twin prime

References