ZetaZero
ZetaZero[k] represents the kth zero of the Riemann zeta function on the critical line.
ZetaZero[k, t] represents the kth zero with imaginary part greater than t.
Examples
N[ZetaZero[1]]
(* 0.5 + 14.1347 I *)Please visit the official Wolfram Language Reference for more details.