Equationally extremal semilattices
  In the current paper we study extremal semilattices with respect to their equational properties. In the class $\mathbf{S}_n$ of all semilattices of order $n$ we find semilattices which have maximal (minimal) number of consistent equations. Moreover, we find a semilattice in $\mathbf{S}_n$ with maximal sum of numbers of solutions of equations. 
Artem N. Shevlyakov
math.RA