Complexity of Mal'cev interpolation

E. Aichinger, D. Mašulović, R. Pöschel

A classical result in near-ring theory tells that the 4-interpolation property implies the n-interpolation property for all $n\in\mathbb N$. In the present note we are interested in the complexity of a special kind of interpolating terms which can be constructed from the 4-interpolations.