On the Singular Part of the Partition Monoid
نویسنده
چکیده
We study the singular part of the partition monoid Pn; that is, the ideal Pn \ Sn, where Sn is the symmetric group. Our main results are presentations in terms of generators and relations, and we also show that Pn \Sn is idempotent generated, and that its rank and idempotent-rank are both equal to ( n+1 2 ) = 12n(n + 1). One of our presentations uses an idempotent generating set of this minimal cardinality.
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ورودعنوان ژورنال:
- IJAC
دوره 21 شماره
صفحات -
تاریخ انتشار 2011