| Title:
             | 
Betti numbers of some circulant graphs (English) | 
| Author:
             | 
Abdi Makvand, Mohsen | 
| Author:
             | 
Mousivand, Amir | 
| Language:
             | 
English | 
| Journal:
             | 
Czechoslovak Mathematical Journal | 
| ISSN:
             | 
0011-4642 (print) | 
| ISSN:
             | 
1572-9141 (online) | 
| Volume:
             | 
69 | 
| Issue:
             | 
3 | 
| Year:
             | 
2019 | 
| Pages:
             | 
593-607 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
Let $o(n)$ be the greatest odd integer less than or equal to $n$. In this paper we provide explicit formulae to compute $\mathbb {N}$-graded Betti numbers of the circulant graphs $C_{2n}(1,2,3,5,\ldots ,o(n))$. We do this by showing that this graph is the product (or join) of the cycle $C_n$ by itself, and computing Betti numbers of $C_n*C_n$. We also discuss whether such a graph (more generally, $G*H$) is well-covered, Cohen-Macaulay, sequentially Cohen-Macaulay, Buchsbaum, or $S_2$. (English) | 
| Keyword:
             | 
Betti number | 
| Keyword:
             | 
Castelnuovo-Mumford regularity | 
| Keyword:
             | 
projective dimension | 
| Keyword:
             | 
circulant graph | 
| MSC:
             | 
05C75 | 
| MSC:
             | 
13D02 | 
| idZBL:
             | 
Zbl 07088806 | 
| idMR:
             | 
MR3989268 | 
| DOI:
             | 
10.21136/CMJ.2019.0606-16 | 
| . | 
| Date available:
             | 
2019-07-24T11:14:08Z | 
| Last updated:
             | 
2021-10-04 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/147778 | 
| . | 
| Reference:
             | 
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