Siggers term

Summary

A Siggers term is an idempotent term of arity $6$ that satisfies one fixed identity in three variables, $s(x, y, x, z, y, z) \approx s(y, x, z, x, z, y)$. Every Siggers term is a Taylor term. Conversely, a finite algebra that has a Taylor term also has a Siggers term, so one explicit identity replaces the whole family of Taylor conditions. This makes the Siggers term a convenient test in the algebraic theory of constraint satisfaction problems.