Residual Complex on the Tangent Cone of a Numerical Semigroup Ring
I-Chiau Huang



A residual complex on the tangent cone of a numerical semigroup ring is constructed in terms of modules of homomorphisms. Macaulay’s inverse system is generalized. Applications of the constructions include a criterion for the Gorensteiness of the tangent cone in terms of the symmetry of the set of basis monomials.