Abstract
We give explicit numerical values with 100 decimal digits for the Mertens constant involved in the asymptotic formula for 1/p and, as a byproduct, for the Meissel-Mertens constant defined as Σ
p≡a mod q
(log(1 − 1/p) + 1/p), for q ∊ {3, …, 100} and (q, a) = 1. The complete set of results is available online (http://www.math.unipd.it/~languasc/Mertens-comput.html).