Journal of Symbolic Computation最新文献

{"title":"Classification of primitive quandles of small order","authors":"Dilpreet Kaur,&nbsp;Pushpendra Singh","doi":"10.1016/j.jsc.2025.102452","DOIUrl":"10.1016/j.jsc.2025.102452","url":null,"abstract":"<div><div>In this article, we describe primitive quandles with the help of primitive permutation groups. As a consequence, we enumerate finite non-affine primitive quandles up to order 4096.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102452"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partial semiorthogonal decompositions for quiver moduli","authors":"Gianni Petrella","doi":"10.1016/j.jsc.2025.102448","DOIUrl":"10.1016/j.jsc.2025.102448","url":null,"abstract":"<div><div>We embed several copies of the derived category of a quiver and certain line bundles in the derived category of an associated moduli space of representations, giving the start of a semiorthogonal decomposition. This mirrors the semiorthogonal decompositions of moduli of vector bundles on curves. Our results are obtained with <span>QuiverTools</span>, an open-source package of tools for quiver representations, their moduli spaces and their geometrical properties.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102448"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143839767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On arrangements of quadrics in decomposing the parameter space of 3D digitized rigid motions","authors":"Kacper Pluta ,&nbsp;Guillaume Moroz ,&nbsp;Yukiko Kenmochi ,&nbsp;Pascal Romon","doi":"10.1016/j.jsc.2025.102447","DOIUrl":"10.1016/j.jsc.2025.102447","url":null,"abstract":"<div><div>Computing the arrangement of quadrics in 3D is a fundamental problem in symbolic computation, with challenges arising when handling degenerate cases and asymptotic critical values. State-of-the-art methods typically require a generic change of coordinates to manage these asymptotes, rendering certain problems intractable. A specific instance of this challenge appears in digital geometry, where comparing 3D shapes up to isometry requires applying a 3D rigid motion on <span><math><msup><mrow><mi>Z</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> and mapping the result back to <span><math><msup><mrow><mi>Z</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span>, a process typically achieved via a digitization operator. However, such motions do not preserve the topology of digital objects, making the analysis of digitized rigid motions crucial. Our main contribution is the decomposition of the 6D parameter space of digitized rigid motions for image patches of radius up to three. This problem reduces to computing the arrangement of up to 741 quadrics, some of which are degenerate. To address the computational challenges, we introduce and implement a new algorithm for computing arrangements of quadrics in 3D, specifically designed to handle degenerate directions and asymptotic critical values. This approach allows us to overcome the limitations of existing methods, making the problem tractable in the context of digital geometry.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102447"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decomposition loci of tensors","authors":"Alessandra Bernardi ,&nbsp;Alessandro Oneto ,&nbsp;Pierpaola Santarsiero","doi":"10.1016/j.jsc.2025.102451","DOIUrl":"10.1016/j.jsc.2025.102451","url":null,"abstract":"<div><div>The decomposition locus of a tensor is the set of rank-one tensors appearing in a minimal tensor-rank decomposition of the tensor. For tensors lying on the tangential variety of any Segre variety, but not on the variety itself, we show that the decomposition locus consists of all rank-one tensors except the tangency point only. We also explicitly compute decomposition loci of all tensors belonging to tensor spaces with finitely many orbits with respect to the action of product of general linear groups.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102451"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Certified simultaneous isotopic approximation of algebraic curves via subdivision","authors":"Michael Burr,&nbsp;Michael Byrd","doi":"10.1016/j.jsc.2025.102435","DOIUrl":"10.1016/j.jsc.2025.102435","url":null,"abstract":"<div><div>We present a certified algorithm based on subdivision for computing an isotopic approximation to any number of algebraic curves in the plane. Our algorithm is based on the certified curve approximation algorithm of Plantinga and Vegter. The main challenge in this algorithm is to correctly and efficiently identify and isolate all intersections between the curves. To overcome this challenge, we introduce a new and simple test that guarantees the global correctness of our output. A main step in our algorithm for approximating any number of curves is to correctly approximate a pair of curves. In addition to developing the details of this special case, we provide complexity analyses for both the number of steps and the bit-complexity of this algorithm using both worst-case bounds as well as those based on continuous amortization and condition numbers.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102435"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elimination by substitution","authors":"Martin Kreuzer ,&nbsp;Lorenzo Robbiano","doi":"10.1016/j.jsc.2025.102445","DOIUrl":"10.1016/j.jsc.2025.102445","url":null,"abstract":"<div><div>Let <em>K</em> be a field and <span><math><mi>P</mi><mo>=</mo><mi>K</mi><mo>[</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>]</mo></math></span>. The technique of elimination by substitution is based on discovering a coherently <span><math><mi>Z</mi><mo>=</mo><mo>(</mo><msub><mrow><mi>z</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>z</mi></mrow><mrow><mi>s</mi></mrow></msub><mo>)</mo></math></span>-separating tuple of polynomials <span><math><mo>(</mo><msub><mrow><mi>f</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>f</mi></mrow><mrow><mi>s</mi></mrow></msub><mo>)</mo></math></span> in an ideal <em>I</em>, i.e., on finding polynomials such that <span><math><msub><mrow><mi>f</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>=</mo><msub><mrow><mi>z</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>−</mo><msub><mrow><mi>h</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> with <span><math><msub><mrow><mi>h</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>∈</mo><mi>K</mi><mo>[</mo><mi>X</mi><mo>∖</mo><mi>Z</mi><mo>]</mo></math></span>. Here we elaborate on this technique in the case when <em>P</em> is non-negatively graded. The existence of a coherently <em>Z</em>-separating tuple is reduced to solving several <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-module membership problems. Best separable re-embeddings, i.e., isomorphisms <span><math><mi>P</mi><mo>/</mo><mi>I</mi><mo>⟶</mo><mi>K</mi><mo>[</mo><mi>X</mi><mo>∖</mo><mi>Z</mi><mo>]</mo><mo>/</mo><mo>(</mo><mi>I</mi><mo>∩</mo><mi>K</mi><mo>[</mo><mi>X</mi><mo>∖</mo><mi>Z</mi><mo>]</mo><mo>)</mo></math></span> with maximal #<em>Z</em>, are found degree-by-degree. They turn out to yield optimal re-embeddings in the positively graded case. Viewing <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>⟶</mo><mi>P</mi><mo>/</mo><mi>I</mi></math></span> as a fibration over an affine space, we show that its fibers allow optimal <em>Z</em>-separating re-embeddings, and we provide a criterion for a fiber to be isomorphic to an affine space. In the last section we introduce a new technique based on the solution of a unimodular matrix problem which enables us to construct automorphisms of <em>P</em> such that additional <em>Z</em>-separating re-embeddings are possible. One of the main outcomes is an algorithm which allows us to explicitly compute a homogeneous isomorphism between <span><math><mi>P</mi><mo>/</mo><mi>I</mi></math></span> and a non-negatively graded polynomial ring if <span><math><mi>P</mi><mo>/</mo><mi>I</mi></math></span> is regular.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"131 ","pages":"Article 102445"},"PeriodicalIF":0.6,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A propositional encoding for first-order clausal entailment over infinitely many constants","authors":"Vaishak Belle","doi":"10.1016/j.jsc.2025.102434","DOIUrl":"10.1016/j.jsc.2025.102434","url":null,"abstract":"<div><div>There is a fundamental trade-off between the expressiveness of the language and the tractability of the reasoning task in knowledge representation. On the one hand it is widely acknowledged that relations and more generally, the expressiveness of first-order logic is extremely useful for capturing concepts required for common-sense reasoning. But at the same time the entailment problem is only semi-decidable.</div><div>There have been a wide range of approaches to deal with this trade-off, from restricting the language to propositional logic to limit the expressiveness of the language in terms of the arity of the predicates (as in description logics) or the use of negation (as in Horn logic) to limit reasoning by weakening the entailment relation using non-standard semantics.</div><div>In this work, we address a gap in this literature. We show that there is an intuitive fragment of first-order disjunctive knowledge, for which reasoning is decidable and can be reduced to propositional satisfiability. Knowledge bases in this fragment correspond to universally quantified first-order clauses, but without arity restrictions and without restrictions on the appearance of negation. Queries, however, are expected to be ground formulas. We achieve this result by showing how the entailment over infinitely many infinite-sized structures can be reduced to a search over finitely many finite-size structures. The crux of the argument lies in showing that constants not mentioned in the knowledge base and/or query behave identically (in a suitable formal sense). We then go on to also show that there is also an extension to this result for function symbols.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"130 ","pages":"Article 102434"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wilf-Zeilberger seeds and non-trivial hypergeometric identities","authors":"Kam Cheong Au","doi":"10.1016/j.jsc.2025.102421","DOIUrl":"10.1016/j.jsc.2025.102421","url":null,"abstract":"<div><div>We introduce a systematic approach for generating Wilf-Zeilberger-pairs, and prove some hypergeometric identities conjectured by J. Guillera, Z.W. Sun, Y. Zhao and others, including two Ramanujan-<span><math><mn>1</mn><mo>/</mo><msup><mrow><mi>π</mi></mrow><mrow><mn>4</mn></mrow></msup></math></span>, one <span><math><mn>1</mn><mo>/</mo><msup><mrow><mi>π</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> formulas as well as a remarkable series for <span><math><mi>ζ</mi><mo>(</mo><mn>5</mn><mo>)</mo></math></span>.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"130 ","pages":"Article 102421"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143176023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First-order factors of linear Mahler operators","authors":"Frédéric Chyzak ,&nbsp;Thomas Dreyfus ,&nbsp;Philippe Dumas ,&nbsp;Marc Mezzarobba","doi":"10.1016/j.jsc.2025.102424","DOIUrl":"10.1016/j.jsc.2025.102424","url":null,"abstract":"<div><div>We develop and compare two algorithms for computing first-order right-hand factors in the ring of linear Mahler operators <span><math><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>r</mi></mrow></msub><msup><mrow><mi>M</mi></mrow><mrow><mi>r</mi></mrow></msup><mo>+</mo><mo>…</mo><mo>+</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mn>1</mn></mrow></msub><mi>M</mi><mo>+</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> where <span><math><msub><mrow><mi>ℓ</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>r</mi></mrow></msub></math></span> are polynomials in <em>x</em> and <span><math><mi>M</mi><mi>x</mi><mo>=</mo><msup><mrow><mi>x</mi></mrow><mrow><mi>b</mi></mrow></msup><mi>M</mi></math></span> for some integer <span><math><mi>b</mi><mo>≥</mo><mn>2</mn></math></span>. In other words, we give algorithms for finding all formal infinite product solutions of linear functional equations <span><math><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>r</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mi>f</mi><mo>(</mo><msup><mrow><mi>x</mi></mrow><mrow><msup><mrow><mi>b</mi></mrow><mrow><mi>r</mi></mrow></msup></mrow></msup><mo>)</mo><mo>+</mo><mo>…</mo><mo>+</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mi>f</mi><mo>(</mo><msup><mrow><mi>x</mi></mrow><mrow><mi>b</mi></mrow></msup><mo>)</mo><mo>+</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mi>f</mi><mo>(</mo><mi>x</mi><mo>)</mo><mo>=</mo><mn>0</mn></math></span>.</div><div>The first of our algorithms is adapted from Petkovšek's classical algorithm for the analogous problem in the case of linear recurrences. The second one proceeds by computing a basis of generalized power series solutions of the functional equation and by using Hermite–Padé approximants to detect those linear combinations of the solutions that correspond to first-order factors.</div><div>We present implementations of both algorithms and discuss their use in combination with criteria from the literature to prove the differential transcendence of power series solutions of Mahler equations.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"130 ","pages":"Article 102424"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143288038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The conjugacy problem and canonical representatives in finitely generated nilpotent groups","authors":"Bettina Eick,&nbsp;Óscar Fernández Ayala","doi":"10.1016/j.jsc.2025.102422","DOIUrl":"10.1016/j.jsc.2025.102422","url":null,"abstract":"<div><div>We introduce a variation on the conjugacy problem for elements and subgroups in a finitely generated nilpotent group <em>G</em> given by a nilpotent presentation and we describe effective algorithms for its solution. While the classical conjugacy problem takes elements or subgroups <em>a</em> and <em>b</em> of <em>G</em> and asks to construct <span><math><mi>g</mi><mo>∈</mo><mi>G</mi></math></span> with <span><math><msup><mrow><mi>a</mi></mrow><mrow><mi>g</mi></mrow></msup><mo>=</mo><mi>b</mi></math></span>, our variation defines and determines a <em>canonical representative</em> <span><math><mi>C</mi><mi>a</mi><mi>n</mi><msub><mrow><mi>o</mi></mrow><mrow><mi>G</mi></mrow></msub><mo>(</mo><mi>a</mi><mo>)</mo></math></span> in <span><math><msup><mrow><mi>a</mi></mrow><mrow><mi>G</mi></mrow></msup></math></span>. This allows to solve the conjugacy problem via an equality test <span><math><mi>C</mi><mi>a</mi><mi>n</mi><msub><mrow><mi>o</mi></mrow><mrow><mi>G</mi></mrow></msub><mo>(</mo><mi>a</mi><mo>)</mo><mo>=</mo><mi>C</mi><mi>a</mi><mi>n</mi><msub><mrow><mi>o</mi></mrow><mrow><mi>G</mi></mrow></msub><mo>(</mo><mi>b</mi><mo>)</mo></math></span>. Additionally, our algorithms compute the associated centralizers or normalizers, respectively. We exhibit a variety of examples to demonstrate that our new methods are highly effective and often outperform the existing methods to solve the conjugacy problems for elements and subgroups in finitely generated nilpotent groups.</div></div>","PeriodicalId":50031,"journal":{"name":"Journal of Symbolic Computation","volume":"130 ","pages":"Article 102422"},"PeriodicalIF":0.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143176022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}