{"id":"https://openalex.org/W2054788067","doi":"https://doi.org/10.1016/s0166-218x(99)00230-9","title":"Cocyclic Hadamard matrices and difference sets","display_name":"Cocyclic Hadamard matrices and difference sets","publication_year":2000,"publication_date":"2000-05-01","ids":{"openalex":"https://openalex.org/W2054788067","doi":"https://doi.org/10.1016/s0166-218x(99)00230-9","mag":"2054788067"},"language":"en","primary_location":{"id":"doi:10.1016/s0166-218x(99)00230-9","is_oa":false,"landing_page_url":"https://doi.org/10.1016/s0166-218x(99)00230-9","pdf_url":null,"source":{"id":"https://openalex.org/S171741597","display_name":"Discrete Applied Mathematics","issn_l":"0166-218X","issn":["0166-218X","1872-6771"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Discrete Applied Mathematics","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5055127288","display_name":"Warwick de Launey","orcid":null},"institutions":[{"id":"https://openalex.org/I3149230897","display_name":"Institute For Defense Analyses","ror":"https://ror.org/00rh8m666","country_code":"US","type":"nonprofit","lineage":["https://openalex.org/I3149230897"]}],"countries":["US"],"is_corresponding":true,"raw_author_name":"Warwick de Launey","raw_affiliation_strings":["Institute of Defense Analysis, San Diego, CA 92121, USA"],"affiliations":[{"raw_affiliation_string":"Institute of Defense Analysis, San Diego, CA 92121, USA","institution_ids":["https://openalex.org/I3149230897"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5074614243","display_name":"Dane Flannery","orcid":"https://orcid.org/0000-0002-9767-7768"},"institutions":[{"id":"https://openalex.org/I188760350","display_name":"Ollscoil na Gaillimhe \u2013 University of Galway","ror":"https://ror.org/03bea9k73","country_code":"IE","type":"education","lineage":["https://openalex.org/I188760350"]}],"countries":["IE"],"is_corresponding":false,"raw_author_name":"D.L. Flannery","raw_affiliation_strings":["Department of Mathematics, National University of Ireland, Galway, Ireland","Department of Mathematics, National University of Ireland, Galway, Ireland#TAB#"],"affiliations":[{"raw_affiliation_string":"Department of Mathematics, National University of Ireland, Galway, Ireland","institution_ids":["https://openalex.org/I188760350"]},{"raw_affiliation_string":"Department of Mathematics, National University of Ireland, Galway, Ireland#TAB#","institution_ids":["https://openalex.org/I188760350"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5058448174","display_name":"K. J. Horadam","orcid":"https://orcid.org/0000-0002-6980-220X"},"institutions":[{"id":"https://openalex.org/I1320473756","display_name":"The Royal Melbourne Hospital","ror":"https://ror.org/005bvs909","country_code":"AU","type":"funder","lineage":["https://openalex.org/I1320473756","https://openalex.org/I4210158168"]}],"countries":["AU"],"is_corresponding":false,"raw_author_name":"K.J. Horadam","raw_affiliation_strings":["Department of Mathematics, Royal Melbourne Institute of Technology, Melbourne, VIC 3001, Australia"],"affiliations":[{"raw_affiliation_string":"Department of Mathematics, Royal Melbourne Institute of Technology, Melbourne, VIC 3001, Australia","institution_ids":["https://openalex.org/I1320473756"]}]}],"institutions":[],"countries_distinct_count":3,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5055127288"],"corresponding_institution_ids":["https://openalex.org/I3149230897"],"apc_list":{"value":2750,"currency":"USD","value_usd":2750},"apc_paid":null,"fwci":4.112,"has_fulltext":false,"cited_by_count":37,"citation_normalized_percentile":{"value":0.93615174,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":89,"max":97},"biblio":{"volume":"102","issue":"1-2","first_page":"47","last_page":"61"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11797","display_name":"graph theory and CDMA systems","score":0.9998999834060669,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11797","display_name":"graph theory and CDMA systems","score":0.9998999834060669,"subfield":{"id":"https://openalex.org/subfields/2208","display_name":"Electrical and Electronic Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11130","display_name":"Coding theory and cryptography","score":0.958299994468689,"subfield":{"id":"https://openalex.org/subfields/1702","display_name":"Artificial Intelligence"},"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/T10849","display_name":"Finite Group Theory Research","score":0.9060999751091003,"subfield":{"id":"https://openalex.org/subfields/2607","display_name":"Discrete Mathematics and Combinatorics"},"field":{"id":"https://openalex.org/fields/26","display_name":"Mathematics"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/hadamard-transform","display_name":"Hadamard transform","score":0.9609442353248596},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.8818671107292175},{"id":"https://openalex.org/keywords/complex-hadamard-matrix","display_name":"Complex Hadamard matrix","score":0.8597909808158875},{"id":"https://openalex.org/keywords/hadamard-matrix","display_name":"Hadamard matrix","score":0.7990602254867554},{"id":"https://openalex.org/keywords/hadamard-three-lines-theorem","display_name":"Hadamard three-lines theorem","score":0.7853516340255737},{"id":"https://openalex.org/keywords/hadamards-inequality","display_name":"Hadamard's inequality","score":0.7806180715560913},{"id":"https://openalex.org/keywords/hadamards-maximal-determinant-problem","display_name":"Hadamard's maximal determinant problem","score":0.7106716632843018},{"id":"https://openalex.org/keywords/equivalence","display_name":"Equivalence (formal languages)","score":0.6131799817085266},{"id":"https://openalex.org/keywords/difference-set","display_name":"Difference set","score":0.49647313356399536},{"id":"https://openalex.org/keywords/automorphism","display_name":"Automorphism","score":0.49472329020500183},{"id":"https://openalex.org/keywords/hadamard-product","display_name":"Hadamard product","score":0.46415480971336365},{"id":"https://openalex.org/keywords/pure-mathematics","display_name":"Pure mathematics","score":0.4416595995426178},{"id":"https://openalex.org/keywords/combinatorics","display_name":"Combinatorics","score":0.4254460036754608},{"id":"https://openalex.org/keywords/discrete-mathematics","display_name":"Discrete mathematics","score":0.41206684708595276},{"id":"https://openalex.org/keywords/mathematical-analysis","display_name":"Mathematical analysis","score":0.14537936449050903}],"concepts":[{"id":"https://openalex.org/C60292330","wikidata":"https://www.wikidata.org/wiki/Q1014065","display_name":"Hadamard transform","level":2,"score":0.9609442353248596},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.8818671107292175},{"id":"https://openalex.org/C6497535","wikidata":"https://www.wikidata.org/wiki/Q5156556","display_name":"Complex Hadamard matrix","level":4,"score":0.8597909808158875},{"id":"https://openalex.org/C30463267","wikidata":"https://www.wikidata.org/wiki/Q1422682","display_name":"Hadamard matrix","level":3,"score":0.7990602254867554},{"id":"https://openalex.org/C68720959","wikidata":"https://www.wikidata.org/wiki/Q3527250","display_name":"Hadamard three-lines theorem","level":4,"score":0.7853516340255737},{"id":"https://openalex.org/C31021346","wikidata":"https://www.wikidata.org/wiki/Q1365087","display_name":"Hadamard's inequality","level":4,"score":0.7806180715560913},{"id":"https://openalex.org/C121334634","wikidata":"https://www.wikidata.org/wiki/Q5637579","display_name":"Hadamard's maximal determinant problem","level":5,"score":0.7106716632843018},{"id":"https://openalex.org/C2780069185","wikidata":"https://www.wikidata.org/wiki/Q7977945","display_name":"Equivalence (formal languages)","level":2,"score":0.6131799817085266},{"id":"https://openalex.org/C188204562","wikidata":"https://www.wikidata.org/wiki/Q5275281","display_name":"Difference set","level":3,"score":0.49647313356399536},{"id":"https://openalex.org/C118712358","wikidata":"https://www.wikidata.org/wiki/Q782566","display_name":"Automorphism","level":2,"score":0.49472329020500183},{"id":"https://openalex.org/C90230998","wikidata":"https://www.wikidata.org/wiki/Q3406746","display_name":"Hadamard product","level":3,"score":0.46415480971336365},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.4416595995426178},{"id":"https://openalex.org/C114614502","wikidata":"https://www.wikidata.org/wiki/Q76592","display_name":"Combinatorics","level":1,"score":0.4254460036754608},{"id":"https://openalex.org/C118615104","wikidata":"https://www.wikidata.org/wiki/Q121416","display_name":"Discrete mathematics","level":1,"score":0.41206684708595276},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.14537936449050903},{"id":"https://openalex.org/C136170076","wikidata":"https://www.wikidata.org/wiki/Q181296","display_name":"Abelian group","level":2,"score":0.0}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1016/s0166-218x(99)00230-9","is_oa":false,"landing_page_url":"https://doi.org/10.1016/s0166-218x(99)00230-9","pdf_url":null,"source":{"id":"https://openalex.org/S171741597","display_name":"Discrete Applied Mathematics","issn_l":"0166-218X","issn":["0166-218X","1872-6771"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Discrete Applied Mathematics","raw_type":"journal-article"},{"id":"pmh:oai:aran.library.nuigalway.ie/:10379/9046","is_oa":false,"landing_page_url":"http://hdl.handle.net/10379/9046","pdf_url":null,"source":{"id":"https://openalex.org/S4377196322","display_name":"ARAN (University of Galway Research Repository) (Ollscoil na Gaillimhe \u2013 University of Galway)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I188760350","host_organization_name":"Ollscoil na Gaillimhe \u2013 University of Galway","host_organization_lineage":["https://openalex.org/I188760350"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":36,"referenced_works":["https://openalex.org/W132765169","https://openalex.org/W163760668","https://openalex.org/W564046778","https://openalex.org/W1502208604","https://openalex.org/W1532853593","https://openalex.org/W1590336317","https://openalex.org/W1593761715","https://openalex.org/W1965142549","https://openalex.org/W1966349643","https://openalex.org/W1967839811","https://openalex.org/W2008952375","https://openalex.org/W2018495157","https://openalex.org/W2028587487","https://openalex.org/W2030141814","https://openalex.org/W2042826512","https://openalex.org/W2046506885","https://openalex.org/W2063465286","https://openalex.org/W2068564568","https://openalex.org/W2080193232","https://openalex.org/W2081376314","https://openalex.org/W2082156999","https://openalex.org/W2087030900","https://openalex.org/W2091001878","https://openalex.org/W2092865667","https://openalex.org/W2114928706","https://openalex.org/W2124117033","https://openalex.org/W2171326554","https://openalex.org/W2611298788","https://openalex.org/W2750866104","https://openalex.org/W2751006412","https://openalex.org/W2752414486","https://openalex.org/W4211147273","https://openalex.org/W4213048462","https://openalex.org/W4254565929","https://openalex.org/W6606751784","https://openalex.org/W6743855221"],"related_works":["https://openalex.org/W2138472192","https://openalex.org/W4226106482","https://openalex.org/W1971692815","https://openalex.org/W1976224891","https://openalex.org/W2170231972","https://openalex.org/W2093489410","https://openalex.org/W2026768906","https://openalex.org/W2072949187","https://openalex.org/W2061168688","https://openalex.org/W2054788067"],"abstract_inverted_index":null,"counts_by_year":[{"year":2025,"cited_by_count":1},{"year":2024,"cited_by_count":1},{"year":2022,"cited_by_count":1},{"year":2021,"cited_by_count":4},{"year":2020,"cited_by_count":1},{"year":2019,"cited_by_count":2},{"year":2018,"cited_by_count":2},{"year":2017,"cited_by_count":2},{"year":2016,"cited_by_count":3},{"year":2015,"cited_by_count":3},{"year":2014,"cited_by_count":3}],"updated_date":"2026-03-10T14:07:55.174380","created_date":"2025-10-10T00:00:00"}