## Nagoya Mathematical Journal

### Shellability of semigroup rings

#### Abstract

The concepts of $\Lambda$-shellability of locally finite posets as well as of extendable sequentially Koszul algebras will be introduced. It will be proved that the divisor poset of a homogeneous semigroup ring is $\Lambda$-shellable if and only if the semigroup ring is extendable sequentially Koszul. Examples of extendable sequentially Koszul semigroup rings contain all monomial ASL's (algebras with straightening laws) and all second squarefree Veronese subrings.

#### Article information

Source
Nagoya Math. J., Volume 168 (2002), 65-84.

Dates
First available in Project Euclid: 27 April 2005

https://projecteuclid.org/euclid.nmj/1114631780

Mathematical Reviews number (MathSciNet)
MR1942394

Zentralblatt MATH identifier
1041.16018

#### Citation

Aramova, Annetta; Herzog, Jürgen; Hibi, Takayuki. Shellability of semigroup rings. Nagoya Math. J. 168 (2002), 65--84. https://projecteuclid.org/euclid.nmj/1114631780

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