There is a connection between the product of the Bell series of two functions and their Dirichlet convolution.
Theorem
Let
and
be arithmetical functions and let
then for every prime
we have![]()
Proof: Since the divisors of
are
we have![]()
The last sum is the Cauchy product of the sequences
and![]()
Examples:
so the Bell series of
modulo
is![]()
so the Bell series of
modulo
is ![]()
Bell series can be used to investigate the properties of arithmetical functions. If
where
and
then
is multiplicative and it's Bell series modulo
is![]()
Hence
which implies
or![]()