A characterization of varieties with a difference term, II: neutral $=$ meet semi-distributive

http://dx.doi.org/10.4153/CMB-1998-044-9
Canad. Math. Bull. 41(1998), 318-327

  Published:1998-09-01
 Printed: Sep 1998

We provide more characterizations of varieties with a weak difference term and of neutral varieties. We prove that a variety has a (weak) difference term (is neutral) with respect to the TC-commutator iff it has a (weak) difference term (is neutral) with respect to the linear commutator. We show that a variety \v\ is congruence meet semi-distributive i{f}f \v\ is neutral, i{f}f $M_3$ is not a sublattice of \con a, for ${\bf A} \in \v$, i{f}f there is a positive integer $n$ such that $\v \smc \a(\b\o\g)\leq\alpha \beta_n$.