  In this work we studied the critical behavior of the critical point as
function of the number of nearest neighbors on two dimensional regular
lattices. We performed numerical simulations on triangular, hexagonal and
bilayer square lattices. Using standard finite size scaling theory we found
that all cases fall in the two dimensional Ising model universality class, but
that the critical point value for the bilayer lattice does not follow the
regular tendency that the Ising model shows.
