We present an efficient explicit mechanism to convert bounds on
to bounds on
and on
.
We use this mechanism in three different ways. We first improve on existing bounds
for
and
;
secondly, we compute the exact value of
and thirdly, we prove that
.
This establishes that the supremum of
is not reached for
,
contrary to what the first numerical observations might suggest.
Keywords
explicit theory of prime numbers, asymptotics of
arithmetical functions