Published online by Cambridge University Press: 09 April 2009
For all positive integers m, n, m ≤ n, let m,n denote the variety of algebras with m n-ary operations ω1, …, ωm and n m-ary operations φ1, …, φn satisfying the system of identities
The varieties
m,n are considered by Swierczkowski [1] and by Akataeb and Smirnov [2]. Jonsson and Tarski [3] consider
m,n in the case m = 1, n = 2. In [2] it is shown that the lattice Lm,n of subvarieties of
m,n, is uncountable except when m = 1 in which case Lm,n has a very simple description. In particular, for n > 1 the lattice L1,n is the two element chain which means that
1,n has no proper subvarieties.