  This paper reports the Feynman-parametric representation of the
vacuum-polarization function consisting of 105 Feynman diagrams of the eighth
order, and its contribution to the gauge-invariant set called Set I(i) of the
tenth-order lepton anomalous magnetic moment. Numerical evaluation of this set
is carried out using FORTRAN codes generated by an automatic code generation
system gencodevpN developed specifically for this purpose. The contribution of
diagrams containing electron loop to the electron g-2 is 0.017 47 (11)
(alpha/pi)^5. The contribution of diagrams containing muon loop is 0.000 001 67
(3) (alpha/pi)^5. The contribution of tau-lepton loop is negligible at present.
The sum of all these terms is 0.017 47 (11) (alpha/pi)^5. The contribution of
diagrams containing electron loop to the muon g-2 is 0.087 1 (59) (alpha/pi)^5.
That of tau-lepton loop is 0.000 237 (1) (alpha/pi)^5. The total contribution
to a_mu, the sum of these terms and the mass-independent term, is 0.104 8 (59)
(alpha/pi)^5.
