论文标题
部分订单
Betweenness of partial orders
论文作者
论文摘要
我们构建了一个单调的二阶句子，该句子是特征的三元关系，这是有限或无限局部订单之间的关系。我们证明没有一阶句子可以做到这一点。我们表征可以从其中间关系中重建的部分订单。我们提出了一种多项式时间算法，该算法测试是否有限关系是部分顺序的中间性。
We construct a monadic second-order sentence that characterizes the ternary relations that are the betweenness relations of finite or infinite partial orders. We prove that no first-order sentence can do that. We characterize the partial orders that can be reconstructed from their betweenness relations. We propose a polynomial time algorithm that tests if a finite relation is the be-tweenness of a partial order.
