The Ninth International Conference on Interactive Theorem Proving (ITP)was held on July 9–12, 2018, in Oxford, UK, as part of the Federated Logic Conference. This special issue of the Journal of Automated Reasoning contains expanded versions of six papers from that conference, chosen by the program committee. All the papers chosen were rated highly in the usual conference review process, but that was not the sole criteria for inclusion. We also looked for work that would benefit from a more expanded, mature treatment, and we aimed for a representative sample of topics. The expanded versions were reviewed according to the usual standards of this journal. Of the six, two belong to the realm of formalized mathematics and verified mathematical computation:

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前言：Interactive Theorem Proving 2018 扩展论文选集

作为联邦逻辑会议的一部分，第九届交互式定理证明国际会议 (ITP) 于 2018 年 7 月 9 日至 12 日在英国牛津举行。本期《自动推理杂志》特刊包含该会议的六篇论文的扩展版本，由程序委员会选择。所有入选的论文在通常的会议审查过程中都得到了高度评​​价，但这并不是入选的唯一标准。我们还寻找可以从更广泛、更成熟的处理中受益的工作，我们的目标是具有代表性的主题样本。扩展版本按照本期刊通常的标准进行审核。在这六个中，有两个属于形式化数学和验证数学计算领域：