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Abstract: We construct an example of a finitely generated ideal of , where is a one-dimensional domain, whose leading terms ideal is not finitely generated. This gives a negative answer to the open question of whether if is a domain with Krull dimension ≤1, then for any finitely generated ideal of , the leading terms ideal of is also finitely generated. Moreover, as a positive part of our answer, we prove that for any one-dimensional domain and any , the ideal of generated by the leading terms of is finitely generated. [Copyright &y& Elsevier]

Abstract: We present a new and simple algorithm for completion of unimodular vectors with entries in a multivariate Laurent polynomial ring over an infinite field . More precisely, given and a unimodular vector (that is, such that ), the algorithm computes a matrix M in whose determinant is a monomial such that , and thus is a completion of to an invertible matrix. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to decipher constructively a lemma of Suslin which played a central role in his second solution of Serre’s problem on projective modules over polynomial rings. This lemma says that for a commutative ring if where is monic and , then there exist such that, denoting by the first coordinate of , we have . By the constructive proof we give, Suslin’s proof of Serre’s problem becomes fully constructive. Moreover, the new method with which we treat this academic example may be a model for miming constructively abstract proofs in which one works modulo a generic maximal ideal in order to prove that an ideal contains 1. [Copyright &y& Elsevier]

We propose to give positive answers to the open questions: is R(X,Y) strong S when R(X) is strong S? is R stably strong S (resp., universally catenary) when R[X] is strong S (resp., catenary)? in case R is obtained by a (T,I,D) construction. The importance of these results is due to the fact that this type of ring is the principal source of counterexamples. Moreover, we give an answer to the open questions: is R〈X1,…,Xn〉 residually Jaffard (resp., totally Jaffard) when R(X1,…,Xn) is ? We construct a three-dimensional local ring R such that R(X1,…,Xn) is totally Jaffard (and hence, residually Jaffard) whereas R〈X1,…,Xn〉 is not residually Jaffard (and hence, not totally Jaffard). [Copyright &y& Elsevier]

Abstract: We give a constructive deciphering for a generalization of the Quillen–Suslin theorem due to Maroscia and Brewer & Costa stating that finitely generated projective modules over , where is a Prüfer domain with Krull dimension , are extended from . [Copyright &y& Elsevier]