Abstract
We use initially regular sequences that consist of linear sums to explore the depth of \(R/I^2\), when I is a monomial ideal in a polynomial ring R. We give conditions under which these linear sums form regular or initially regular sequences on \(R/I^2\). We then obtain a criterion for when \({{\,\mathrm{depth}\,}}R/I^2>1\) and a lower bound on \({{\,\mathrm{depth}\,}}R/I^2\).
Similar content being viewed by others
References
Adams, W.W., Loustaunau, P.: An introduction to Gröbner bases. Graduate Studies in Mathematics, vol. 3, xiv+289 pp. American Mathematical Society, Providence, RI (1994)
Bandari, S., Herzog, J., Hibi, T.: Monomial ideals whose depth function has any given number of strict local maxima. Ark. Math. 52, 11–19 (2014)
Chen, J., Morey, S., Sung, A.: The stable set of associated primes of the ideal of a graph. Rocky Mt J. Math. 32(1), 71–89 (2002)
Faridi, S.: Monomial ideals via square-free monomial ideals. In: Commutative Algebra, Lect. Notes Pure Appl. Math., vol. 244, pp. 85–114. Chapman & Hall/CRC, Boca Raton, FL (2006)
Francisco, C.A., Hà, H.T., Van Tuyl, A.: Colorings of hypergraphs, perfect graphs, and associated primes of powers of monomial ideals. J. Algebra 331, 224–242 (2011)
Fouli, L., Hà, H.T., Morey, S.: Depth of powers of squarefree monomial ideals (research). In: Advances in Mathematical Sciences, Association for Women in Mathematics Series, vol. 21, pp. 161–171. Springer, Cham (2020)
Fouli, L., Hà, H.T., Morey, S.: Initially regular sequences and depth of ideals. J. Algebra 559, 33–57 (2020)
Fouli, L., Morey, S.: A lower bound for depths of powers of edge ideals. J. Algebraic Combin. 42(3), 829–848 (2015)
Grayson, D.R., Stillman, M.E.: Macaulay2, a software system for research in algebraic geometry. Available at https://faculty.math.illinois.edu/Macaulay2/
Hà, H.T., Nguyen, H.D., Trung, N.V., Trung, T.N.: Depth functions of powers of homogeneous ideals. Proc. Amer. Math. Soc. 149(5), 1837–1844 (2021)
Herzog, J., Hibi, T.: The depth of powers of an ideal. J. Algebra 291(2), 534–550 (2005)
Herzog, J., Vladiou, M.: Squarefree monomial ideals with constant depth function. J. Pure Appl. Algebra 217(9), 1764–1772 (2013)
Lam, H.M., Trung, N.V.: Associated primes of powers of edge ideals and ear decompositions of graphs. Trans. Amer. Math. Soc. 372(5), 3211–3236 (2019)
Morey, S.: Depths of powers of the edge ideal of a tree. Comm. Algebra 38(11), 4042–4055 (2010)
Simis, A., Vasconcelos, W., Villarreal, R.H.: On the ideal theory of graphs. J. Algebra 167(2), 389–416 (1994)
Terai, N., Trung, N.V.: On the associated primes and the depth of the second power of squarefree monomial ideals. J. Pure Appl. Algebra 218(6), 1117–1129 (2014)
Trung, T.N.: Stability of depths of powers of edge ideals. J. Algebra 452, 157–187 (2016)
Villarreal, R.H.: Cohen-Macaulay graphs. Manuscr. Math. 66, 277–293 (1990)
Villarreal, R.H.: Monomial algebras. In: Monographs and Textbooks in Pure and Applied Mathematics, vol. 238, x+455 pp. Marcel Dekker Inc., New York (2001)
Acknowledgements
The authors would like to thank the referees for the careful review of the article and for the suggestions that improved the article. The second author is partially supported by Simons Foundation and Louisiana Board of Regents.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
Additional information
Communicated by Isidoro Gitler.
Dedicated to Rafael H. Villarreal on the occasion of his 70th birthday.
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Fouli, L., Hà, T.H. & Morey, S. Regular sequences on squares of monomial ideals. São Paulo J. Math. Sci. 17, 122–146 (2023). https://doi.org/10.1007/s40863-022-00337-5
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40863-022-00337-5