{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T08:41:47Z","timestamp":1774946507097,"version":"3.50.1"},"reference-count":0,"publisher":"Centre pour la Communication Scientifique Directe (CCSD)","license":[{"start":{"date-parts":[[2007,11,6]],"date-time":"2007-11-06T00:00:00Z","timestamp":1194307200000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/arxiv.org\/licenses\/assumed-1991-2003"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>We describe simple algebraic and combinatorial characterisations of finite\nrelational core structures admitting finitely many obstructions. As a\nconsequence, we show that it is decidable to determine whether a constraint\nsatisfaction problem is first-order definable: we show the general problem to\nbe NP-complete, and give a polynomial-time algorithm in the case of cores. A\nslight modification of this algorithm provides, for first-order definable\nCSP's, a simple poly-time algorithm to produce a solution when one exists. As\nan application of our algebraic characterisation of first order CSP's, we\ndescribe a large family of L-complete CSP's.<\/jats:p>","DOI":"10.2168\/lmcs-3(4:6)2007","type":"journal-article","created":{"date-parts":[[2008,6,3]],"date-time":"2008-06-03T13:13:18Z","timestamp":1212498798000},"source":"Crossref","is-referenced-by-count":25,"title":["A Characterisation of First-Order Constraint Satisfaction Problems"],"prefix":"10.46298","volume":"Volume 3, Issue 4","author":[{"given":"Benoit","family":"Larose","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cynthia","family":"Loten","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claude","family":"Tardif","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"25203","published-online":{"date-parts":[[2007,11,6]]},"container-title":["Logical Methods in Computer Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/lmcs.episciences.org\/1097\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/lmcs.episciences.org\/1097\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,4,11]],"date-time":"2023-04-11T20:03:17Z","timestamp":1681243397000},"score":1,"resource":{"primary":{"URL":"https:\/\/lmcs.episciences.org\/1097"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2007,11,6]]},"references-count":0,"URL":"https:\/\/doi.org\/10.2168\/lmcs-3(4:6)2007","relation":{"is-same-as":[{"id-type":"arxiv","id":"0707.2562","asserted-by":"subject"},{"id-type":"doi","id":"10.48550\/arXiv.0707.2562","asserted-by":"subject"}]},"ISSN":["1860-5974"],"issn-type":[{"value":"1860-5974","type":"electronic"}],"subject":[],"published":{"date-parts":[[2007,11,6]]},"article-number":"1097"}}