Discriminator positively complete classes of ternary logic
Sergey Seraphimovich Marchenkov · Journal of Applied and Industrial Mathematics · 2008
The article addresses the operator of positive closure on the set P k of functions of k-valued logic. For each k ⩾ 3, k ≠ 4, the set H k of all homogeneous functions from P k is proved to form an atom in the lattice of the positively closed classes from P k . Also, we find all 17 positively closed classes from P 3 containing the class H 3 (i.e., discriminator positively closed classes). Positively generating systems of these classes are defined.