Abstract:
It is shown that a variety generated by a nilpotent $A$-loop has a decidable equational (quasiequational) theory. Thereby the question posed by A. I. Mal'tsev in [Mat. Sb., 69(111), № 1 (1966), 3–12] is answered in the negative, and moreover, a finitely presented nilpotent $A$-loop has a decidable word problem.
Keywords:equational theory, nilpotent $A$-loop, word problem.