  Spinfoam amplitudes with small spins can have interesting semiclassical
behavior and relate to semiclassical gravity and geometry in 4 dimensions. We
study the generalized spinfoam model (Spinfoams for all loop quantum gravity
(LQG)) with small spins $j$ but a large number of spin degrees of freedom
(DOFs), and find that it relates to the simplicial
Engle-Pereira-Rovelli-Livine-Freidel-Krasnov (EPRL-FK) model with large spins
and Regge calculus by coarse-graining spin DOFs. Small-$j$ generalized spinfoam
amplitudes can be employed to define semiclassical states in the LQG
kinematical Hilbert space. Each of these semiclassical states is determined by
a 4-dimensional Regge geometry. We compute the entanglement R\'enyi entropies
of these semiclassical states. The entanglement entropy interestingly
coarse-grains spin DOFs in the generalized spinfoam model, and satisfies an
analog of the thermodynamical first law. This result possibly relates to the
quantum black hole thermodynamics in arXiv:1107.1320.
