  We present accurate analytic fitting formulae for the frequency integrated
Gaunt factors for the relativistic as well as nonrelativistic thermal
bremsstrahlung which is relevant to the intracluster plasma. The fitting is
carried out for 1 =< Zj =< 28, 6.0 < log T < 8.5, where Zj is the charge number
of the ion, and T is the electron temperature in kelvins. The present analytic
fitting formulae will be useful for the analysis of the X-ray emission which
comes from the intracluster plasma as well as the other X-ray sources.
