Primordial Non-Gaussianity from G-inflation
  Enormous information about interactions is contained in the non-Gaussianities
of the primordial curvature perturbations, which are essential to break the
degeneracy of inflationary models. We study the primordial bispectra for
G-inflation models predicting both sharp and broad peaks in the primordial
scalar power spectrum. We calculate the non-Gaussianity parameter
$f_{\mathrm{NL}}$ in the equilateral limit and squeezed limit numerically, and
confirm that the consistency relation holds in these models. Even though
$f_{\mathrm{NL}}$ becomes large at the scales before the power spectrum reaches
the peak and the scales where there are wiggles in the power spectrum, it
remains to be small at the peak scales. Therefore, the contributions of
non-Gaussianity to the scalar induced secondary gravitational waves and
primordial black hole abundance are expected to be negligible.
