Finite models are one-generated
 
Every finite model is definitionally equivalent to a model  with a
single relation and, although on a fixed non-empty  finite set there
are infinitely many different relations (the arity of a relation
may be arbitrarily large), the number of definitionally
non-equivalent finite models  with the same universe is finite. In
cylindric  algebraic terms, the result is the infinite dimensional
counterpart of the result proved by S. Comer, H. Andréka and
I. Németi according to which any n-dimensional cylindric  set
algebra with base of power < n+2 can be generated by  a single
element, if n is finite.