标题： 迭代类强迫 显示英文标题

标题： Iterated Class Forcing

摘要： 在本文中，我们分离了分层类强迫的概念，并证明分层性意味着共尾性保持，并且在使用适当支撑的迭代中被保留。许多熟悉的类强迫是分层的，因此可以同时迭代而不改变共尾性，前提是使用适当的支撑。Easton强迫、向后Easton强迫以及Jensen编码的一些修改是分层的。Jensen编码不是分层的，而是服从一个相关性质，即Delta-分层性，这种性质在使用适当更大的支撑进行迭代时也被保留。 显示英文摘要

摘要： In this paper we isolate the notion of Stratified class forcing and show that Stratification implies cofinality-preservation and is preserved by iterations with the appropriate support. Many familiar class forcings are stratified and therefore can be simultaneously iterated without changing cofinalities, provided the proper support is used. Easton forcing, Backward Easton forcings and some modifications of Jensen coding are stratified. Jensen coding is not stratified but instead obeys a related property, Delta-Stratification, which is also preservedby iteration with an appropriate larger support.