摘要
就Ｆｉｘｅｄ Ｐｏｉｎｔ ｉｎ Ｐｏｓｅｔ中的定理“有限偏序集Ｐ是可拆的充要条件为Ｐ是不可约可拆”进行了改进，得到了Ｐ是同伦可拆的充要条件为Ｐ是星形不可约可拆，并且证明了这两个充要条件等价。
Improves the theorem “A finite poset is dismantlable if and only if it is dismantlable by irreducibles”, obtains a new theorem “A finite poset is homotopic dismantlable if and only if it is dismantlable by star irreducibles” and proves the equivalence of these theorems. So greatly simplifies the judgment of dismantlable by irreducibles.
出处
《上海师范大学学报（自然科学版）》
1999年第2期30-33,共4页
Journal of Shanghai Normal University(Natural Sciences)
关键词
不可约元
星形不可约元
可拆
不可约可拆
星形不可约可拆
同伦可拆
irreducible
star irreducible
dismantlable
dismantlable by irreducibles
dismantlable by star irreducibles
homotopic dismantlable
