  Li showed that the Riemann Hypothesis is equivalent to the nonnegativity of a
certain sequence of numbers. Bombieri and Lagarias gave an arithmetic formula
for the number sequence based on the Guinand-Weil explicit formula and showed
that Li's criterion is equivalent to Weil's criterion for the Riemann
Hypothesis. We provide a derivation of the explicit formula based on Laplace
transforms and present an alternative expression for Li's criterion that
invites a probabilistic interpretation.
