Marilena Crupi

Cohen-Macaulay edge ideal whose height is half of the number of vertices

We consider a class of graphs

Extremal Betti numbers of graded ideals

G

Closed graphs are proper interval graphs

such that the height of the edge ideal

Effective Cowsik–Nori Theorem for Edge Ideals

I(G)

Upper bounds for the betti numbers of graded ideals of a given length in the exterior algebra

is half of the number

SQUAREFREE MONOMIAL MODULES AND EXTREMAL BETTI NUMBERS

\sharp V(G)

Classes of Graded Ideals with Given Data in the Exterior Algebra

of the vertices. We give Cohen-Macaulay criteria for such graphs.

Closed orders and closed graphs

The possible extremal Betti numbers of graded ideals in the polynomial ring K[x1,…,xn] in n variables with coefficients in a field K are studied, completing our results in [7]. In case char(K) = 0 we determine, given any integers r < n, the conditions under which there exists a graded ideal I ⊂ K[x1,…, xn] with extremal Betti numbers % MathType!MTEF!2!1!+-% feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXanrfitLxBI9gBaerbd9wDYLwzYbItLDharqqt% ubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq% -Jc9vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0x% fr-xfr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyuam% aaBaaaleaacaaIXaGaaGimaaqabaGccqGH9aqpciGGSbGaaiOBaiaa% ysW7caWGRbWaaSbaaSqaaiaadsfacaaIXaaabeaakiaac+cacaWGRb% WaaSbaaSqaaiaadsfacaaIYaaabeaakiabg2da9iabgkHiTmaabmaa% baGaamyramaaBaaaleaacaWGHbaabeaakiaac+cacaWGsbaacaGLOa% GaayzkaaGaey41aq7aaiWaaeaadaqadaqaaiaadsfadaWgaaWcbaGa% aGOmaaqabaGccqGHsislcaWGubWaaSbaaSqaaiaaigdaaeqaaaGcca% GLOaGaayzkaaGaai4laiaacIcacaWGubWaaSbaaSqaaiaaikdaaeqa% aOGaaGjbVlaadsfadaWgaaWcbaGaamysaaqabaGccaGGPaaacaGL7b% GaayzFaaaaaa!5C4A!

Ideals generated by reverse lexicographic segments

\beta_{k_{i}k_{i}+\ell_{i}}\ {\rm for}\ i=1,\cdots,r

Integrable derivations and formal groups in unequal characteristic

. We also treat a similar problem for squarefree lexsegment ideals.