论文标题
直接链的兄弟姐妹
Siblings of Direct Sums of Chains
论文作者
论文摘要
我们证明，可数的直接链条具有一个，次数很多，或者连续许多兄弟姐妹的同构类别。这证明了Thomassé对此类结构的猜想。此外，我们表明，任何基数的链条直接具有一个或无限的兄弟姐妹，直到同构。
We prove that a countable direct sum of chains has either one, countably many or else continuum many isomorphism classes of siblings. This proves Thomassé's conjecture for such structures. Further, we show that a direct sum of chains of any cardinality has one or infinitely many siblings, up to isomorphism.
