There is a connection between the product of the Bell series of two functions and their Dirichlet convolution.
Theorem
Letandbe arithmetical functions and letthen for every primewe have
Proof: Since the divisors ofarewe have
The last sum is the Cauchy product of the sequencesand
Examples:
so the Bell series ofmodulois
so the Bell series ofmodulois
Bell series can be used to investigate the properties of arithmetical functions. Ifwhere andthenis multiplicative and it's Bell series modulois
Hencewhich impliesor