{"id":"https://openalex.org/W1983788780","doi":"https://doi.org/10.1137/080738866","title":"Retractions to Pseudoforests","display_name":"Retractions to Pseudoforests","publication_year":2010,"publication_date":"2010-01-01","ids":{"openalex":"https://openalex.org/W1983788780","doi":"https://doi.org/10.1137/080738866","mag":"1983788780"},"language":"en","primary_location":{"id":"doi:10.1137/080738866","is_oa":false,"landing_page_url":"https://doi.org/10.1137/080738866","pdf_url":null,"source":{"id":"https://openalex.org/S117679221","display_name":"SIAM Journal on Discrete Mathematics","issn_l":"0895-4801","issn":["0895-4801","1095-7146"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320508","host_organization_name":"Society for Industrial and Applied Mathematics","host_organization_lineage":["https://openalex.org/P4310320508"],"host_organization_lineage_names":["Society for Industrial and Applied Mathematics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"SIAM Journal on Discrete Mathematics","raw_type":"journal-article"},"type":"retraction","indexed_in":["crossref"],"open_access":{"is_oa":true,"oa_status":"green","oa_url":"https://durham-repository.worktribe.com/output/1515767","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5109192583","display_name":"Tom\u00e1s Feder","orcid":null},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Tom\u00e1s Feder","raw_affiliation_strings":["tomas@theory.stanford.edu#TAB#"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"tomas@theory.stanford.edu#TAB#","institution_ids":[]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5075416144","display_name":"Pavol Hell","orcid":"https://orcid.org/0000-0001-7609-9746"},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Pavol Hell","raw_affiliation_strings":["pavol@cs.sfu.ca#TAB#"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"pavol@cs.sfu.ca#TAB#","institution_ids":[]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5101920004","display_name":"Peter J\u00f6nsson","orcid":"https://orcid.org/0000-0002-5288-3330"},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Peter Jonsson","raw_affiliation_strings":["petej@ida.liu.se and gusno@ida.liu.se#TAB#"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"petej@ida.liu.se and gusno@ida.liu.se#TAB#","institution_ids":[]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5003558662","display_name":"Andrei Krokhin","orcid":"https://orcid.org/0000-0003-4373-8227"},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Andrei Krokhin","raw_affiliation_strings":["andrei.krokhin@durham.ac.uk#TAB#"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"andrei.krokhin@durham.ac.uk#TAB#","institution_ids":[]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5007869716","display_name":"Gustav Nordh","orcid":null},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Gustav Nordh","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]}],"institutions":[],"countries_distinct_count":0,"institutions_distinct_count":0,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":null,"apc_paid":null,"fwci":null,"has_fulltext":false,"cited_by_count":30,"citation_normalized_percentile":null,"cited_by_percentile_year":null,"biblio":{"volume":"24","issue":"1","first_page":"101","last_page":"112"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10374","display_name":"Advanced Graph Theory Research","score":0.9995999932289124,"subfield":{"id":"https://openalex.org/subfields/1703","display_name":"Computational Theory and Mathematics"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10374","display_name":"Advanced Graph Theory Research","score":0.9995999932289124,"subfield":{"id":"https://openalex.org/subfields/1703","display_name":"Computational Theory and Mathematics"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11596","display_name":"Constraint Satisfaction and Optimization","score":0.9954000115394592,"subfield":{"id":"https://openalex.org/subfields/1705","display_name":"Computer Networks and Communications"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11567","display_name":"semigroups and automata theory","score":0.9793999791145325,"subfield":{"id":"https://openalex.org/subfields/1703","display_name":"Computational Theory and Mathematics"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.7495853900909424},{"id":"https://openalex.org/keywords/constraint-satisfaction-problem","display_name":"Constraint satisfaction problem","score":0.6507869958877563},{"id":"https://openalex.org/keywords/combinatorics","display_name":"Combinatorics","score":0.58349609375},{"id":"https://openalex.org/keywords/graph","display_name":"Graph","score":0.5364212989807129},{"id":"https://openalex.org/keywords/discrete-mathematics","display_name":"Discrete mathematics","score":0.4987053871154785},{"id":"https://openalex.org/keywords/algebraic-number","display_name":"Algebraic number","score":0.4516250491142273}],"concepts":[{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.7495853900909424},{"id":"https://openalex.org/C199622910","wikidata":"https://www.wikidata.org/wiki/Q1128326","display_name":"Constraint satisfaction problem","level":3,"score":0.6507869958877563},{"id":"https://openalex.org/C114614502","wikidata":"https://www.wikidata.org/wiki/Q76592","display_name":"Combinatorics","level":1,"score":0.58349609375},{"id":"https://openalex.org/C132525143","wikidata":"https://www.wikidata.org/wiki/Q141488","display_name":"Graph","level":2,"score":0.5364212989807129},{"id":"https://openalex.org/C118615104","wikidata":"https://www.wikidata.org/wiki/Q121416","display_name":"Discrete mathematics","level":1,"score":0.4987053871154785},{"id":"https://openalex.org/C9376300","wikidata":"https://www.wikidata.org/wiki/Q168817","display_name":"Algebraic number","level":2,"score":0.4516250491142273},{"id":"https://openalex.org/C49937458","wikidata":"https://www.wikidata.org/wiki/Q2599292","display_name":"Probabilistic logic","level":2,"score":0.0},{"id":"https://openalex.org/C105795698","wikidata":"https://www.wikidata.org/wiki/Q12483","display_name":"Statistics","level":1,"score":0.0},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.0}],"mesh":[],"locations_count":4,"locations":[{"id":"doi:10.1137/080738866","is_oa":false,"landing_page_url":"https://doi.org/10.1137/080738866","pdf_url":null,"source":{"id":"https://openalex.org/S117679221","display_name":"SIAM Journal on Discrete Mathematics","issn_l":"0895-4801","issn":["0895-4801","1095-7146"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320508","host_organization_name":"Society for Industrial and Applied Mathematics","host_organization_lineage":["https://openalex.org/P4310320508"],"host_organization_lineage_names":["Society for Industrial and Applied Mathematics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"SIAM Journal on Discrete Mathematics","raw_type":"journal-article"},{"id":"pmh:oai:CiteSeerX.psu:10.1.1.142.2492","is_oa":false,"landing_page_url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.142.2492","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"http://theory.stanford.edu/~tomas/retractpforest.pdf","raw_type":"text"},{"id":"pmh:oai:CiteSeerX.psu:10.1.1.218.4908","is_oa":false,"landing_page_url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.218.4908","pdf_url":null,"source":null,"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"http://www.ida.liu.se/~gusno/retractpforest2.pdf","raw_type":"text"},{"id":"pmh:oai:durham-repository.worktribe.com:1515767","is_oa":true,"landing_page_url":"https://durham-repository.worktribe.com/output/1515767","pdf_url":null,"source":{"id":"https://openalex.org/S4306400188","display_name":"Durham Research Online (Durham University)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I190082696","host_organization_name":"Durham University","host_organization_lineage":["https://openalex.org/I190082696"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Journal Article"}],"best_oa_location":{"id":"pmh:oai:durham-repository.worktribe.com:1515767","is_oa":true,"landing_page_url":"https://durham-repository.worktribe.com/output/1515767","pdf_url":null,"source":{"id":"https://openalex.org/S4306400188","display_name":"Durham Research Online (Durham University)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I190082696","host_organization_name":"Durham University","host_organization_lineage":["https://openalex.org/I190082696"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Journal Article"},"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":16,"referenced_works":["https://openalex.org/W655258421","https://openalex.org/W1589711670","https://openalex.org/W1984074081","https://openalex.org/W1984264511","https://openalex.org/W1997649256","https://openalex.org/W2026753685","https://openalex.org/W2033470072","https://openalex.org/W2049582355","https://openalex.org/W2051028069","https://openalex.org/W2077575555","https://openalex.org/W2094346430","https://openalex.org/W2116407296","https://openalex.org/W2132911512","https://openalex.org/W2150339067","https://openalex.org/W2166566648","https://openalex.org/W2504299149"],"related_works":["https://openalex.org/W2000144448","https://openalex.org/W2071261821","https://openalex.org/W1978699240","https://openalex.org/W2067133893","https://openalex.org/W2287003313","https://openalex.org/W2122098529","https://openalex.org/W2374778222","https://openalex.org/W2388103776","https://openalex.org/W2000962138","https://openalex.org/W2036334548"],"abstract_inverted_index":{"For":[0],"a":[1,13,30,45],"fixed":[2],"graph":[3,16,31],"H,":[4],"let":[5],"$\\textsc{Ret}(H)$":[6,26,57],"denote":[7],"the":[8,23,52,84],"problem":[9],"of":[10,25,56,86],"deciding":[11],"whether":[12],"given":[14],"input":[15],"is":[17,29,68],"retractable":[18],"to":[19,63],"H.":[20],"We":[21],"classify":[22],"complexity":[24,54,85],"when":[27],"H":[28],"(with":[32],"loops":[33],"allowed)":[34],"where":[35],"each":[36],"connected":[37],"component":[38],"has":[39],"at":[40],"most":[41],"one":[42],"cycle,":[43],"i.e.,":[44],"pseudoforest.":[46],"In":[47],"particular,":[48],"this":[49],"result":[50],"extends":[51],"known":[53],"classifications":[55],"for":[58,82],"reflexive":[59],"and":[60],"irreflexive":[61],"cycles":[62],"general":[64],"cycles.":[65],"Our":[66],"approach":[67],"based":[69],"mainly":[70],"on":[71],"algebraic":[72],"techniques":[73],"from":[74],"universal":[75],"algebra":[76],"that":[77],"previously":[78],"have":[79],"been":[80],"used":[81],"analyzing":[83],"constraint":[87],"satisfaction":[88],"problems.":[89]},"counts_by_year":[{"year":2022,"cited_by_count":2},{"year":2021,"cited_by_count":1},{"year":2020,"cited_by_count":1},{"year":2019,"cited_by_count":4},{"year":2018,"cited_by_count":2},{"year":2017,"cited_by_count":2},{"year":2016,"cited_by_count":1},{"year":2015,"cited_by_count":2},{"year":2014,"cited_by_count":1},{"year":2013,"cited_by_count":5},{"year":2012,"cited_by_count":7}],"updated_date":"2026-07-14T23:27:15.235271","created_date":"2025-10-10T00:00:00"}