Mitschke's theorem is sharp (Q2073369)

\textit{A. Mitschke} [ibid. 8, 29--32 (1978; Zbl 0368.08003)] showed that a variety with an \(m\)-ary near-unanimity term has Jonsson terms \(t_0,\dots,t_{2m-4}\) witnessing congruence distributivity. The author shows that this result is sharp using a construction of the variety which does not has less of these Jonsson terms. He also evaluates the best possible number of Day terms witnessing congruence modularity.