We consider the following practical question: given a finite algebra A in a finite language, can we efficiently decide whether the variety generated by A has a difference term? We answer this question (positively) in the idempotent case and then describe algorithms for constructing difference term operations.

中文翻译：

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幂等变异项的多项式时间检验

我们考虑以下实际问题：给定有限语言中的有限代数 A，我们能否有效地确定由 A 生成的多样性是否具有差异项？我们在幂等情况下（肯定地）回答这个问题，然后描述构造差分项操作的算法。