{"id":"https://openalex.org/W2040687693","doi":"https://doi.org/10.1007/s10623-011-9493-1","title":"New restrictions on possible orders of circulant Hadamard matrices","display_name":"New restrictions on possible orders of circulant Hadamard matrices","publication_year":2011,"publication_date":"2011-03-13","ids":{"openalex":"https://openalex.org/W2040687693","doi":"https://doi.org/10.1007/s10623-011-9493-1","mag":"2040687693"},"language":"en","primary_location":{"id":"doi:10.1007/s10623-011-9493-1","is_oa":false,"landing_page_url":"https://doi.org/10.1007/s10623-011-9493-1","pdf_url":null,"source":{"id":"https://openalex.org/S81616010","display_name":"Designs Codes and Cryptography","issn_l":"0925-1022","issn":["0925-1022","1573-7586"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319965","host_organization_name":"Springer Nature","host_organization_lineage":["https://openalex.org/P4310319965"],"host_organization_lineage_names":["Springer Nature"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Designs, Codes and Cryptography","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/A5027255093","display_name":"Ka Hin Leung","orcid":"https://orcid.org/0000-0001-5865-139X"},"institutions":[{"id":"https://openalex.org/I165932596","display_name":"National University of Singapore","ror":"https://ror.org/01tgyzw49","country_code":"SG","type":"education","lineage":["https://openalex.org/I165932596"]}],"countries":["SG"],"is_corresponding":true,"raw_author_name":"Ka Hin Leung","raw_affiliation_strings":["Department of Mathematics, National University of Singapore, Kent Ridge, Singapore, 119260, Republic of Singapore","Department of Mathematics, National University of Singapore, Singapore, Republic of Singapore 119260#TAB#"],"affiliations":[{"raw_affiliation_string":"Department of Mathematics, National University of Singapore, Kent Ridge, Singapore, 119260, Republic of Singapore","institution_ids":["https://openalex.org/I165932596"]},{"raw_affiliation_string":"Department of Mathematics, National University of Singapore, Singapore, Republic of Singapore 119260#TAB#","institution_ids":["https://openalex.org/I165932596"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5103242067","display_name":"Bernhard Schmidt","orcid":"https://orcid.org/0000-0003-0560-3946"},"institutions":[{"id":"https://openalex.org/I172675005","display_name":"Nanyang Technological University","ror":"https://ror.org/02e7b5302","country_code":"SG","type":"education","lineage":["https://openalex.org/I172675005"]}],"countries":["SG"],"is_corresponding":false,"raw_author_name":"Bernhard Schmidt","raw_affiliation_strings":["Division of Mathematical Sciences, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Republic of Singapore","Division of Mathematical Sciences, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, Republic of Singapore 637371#TAB#"],"affiliations":[{"raw_affiliation_string":"Division of Mathematical Sciences, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Republic of Singapore","institution_ids":["https://openalex.org/I172675005"]},{"raw_affiliation_string":"Division of Mathematical Sciences, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore, Republic of Singapore 637371#TAB#","institution_ids":["https://openalex.org/I172675005"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":["https://openalex.org/A5027255093"],"corresponding_institution_ids":["https://openalex.org/I165932596"],"apc_list":{"value":2290,"currency":"EUR","value_usd":2890},"apc_paid":null,"fwci":5.6688,"has_fulltext":false,"cited_by_count":43,"citation_normalized_percentile":{"value":0.96186518,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":89,"max":99},"biblio":{"volume":"64","issue":"1-2","first_page":"143","last_page":"151"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11797","display_name":"graph theory and CDMA systems","score":1.0,"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":1.0,"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":0.9955000281333923,"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/T12504","display_name":"Mathematics and Applications","score":0.9544000029563904,"subfield":{"id":"https://openalex.org/subfields/2608","display_name":"Geometry and Topology"},"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/circulant-matrix","display_name":"Circulant matrix","score":0.8675365447998047},{"id":"https://openalex.org/keywords/hadamard-transform","display_name":"Hadamard transform","score":0.8234617710113525},{"id":"https://openalex.org/keywords/conjecture","display_name":"Conjecture","score":0.798503041267395},{"id":"https://openalex.org/keywords/hadamard-matrix","display_name":"Hadamard matrix","score":0.7468217611312866},{"id":"https://openalex.org/keywords/descent","display_name":"Descent (aeronautics)","score":0.7306036353111267},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.6370810866355896},{"id":"https://openalex.org/keywords/hadamard-three-lines-theorem","display_name":"Hadamard three-lines theorem","score":0.626429557800293},{"id":"https://openalex.org/keywords/complex-hadamard-matrix","display_name":"Complex Hadamard matrix","score":0.5781204700469971},{"id":"https://openalex.org/keywords/sequence","display_name":"Sequence (biology)","score":0.5485520958900452},{"id":"https://openalex.org/keywords/field","display_name":"Field (mathematics)","score":0.5158268809318542},{"id":"https://openalex.org/keywords/combinatorics","display_name":"Combinatorics","score":0.48223456740379333},{"id":"https://openalex.org/keywords/hadamards-maximal-determinant-problem","display_name":"Hadamard's maximal determinant problem","score":0.4611665606498718},{"id":"https://openalex.org/keywords/matrix","display_name":"Matrix (chemical analysis)","score":0.424307644367218},{"id":"https://openalex.org/keywords/pure-mathematics","display_name":"Pure mathematics","score":0.3416176736354828},{"id":"https://openalex.org/keywords/discrete-mathematics","display_name":"Discrete mathematics","score":0.3319091498851776},{"id":"https://openalex.org/keywords/physics","display_name":"Physics","score":0.09181344509124756},{"id":"https://openalex.org/keywords/mathematical-analysis","display_name":"Mathematical analysis","score":0.07854732871055603}],"concepts":[{"id":"https://openalex.org/C115973184","wikidata":"https://www.wikidata.org/wiki/Q245457","display_name":"Circulant matrix","level":2,"score":0.8675365447998047},{"id":"https://openalex.org/C60292330","wikidata":"https://www.wikidata.org/wiki/Q1014065","display_name":"Hadamard transform","level":2,"score":0.8234617710113525},{"id":"https://openalex.org/C2780990831","wikidata":"https://www.wikidata.org/wiki/Q319141","display_name":"Conjecture","level":2,"score":0.798503041267395},{"id":"https://openalex.org/C30463267","wikidata":"https://www.wikidata.org/wiki/Q1422682","display_name":"Hadamard matrix","level":3,"score":0.7468217611312866},{"id":"https://openalex.org/C2776637919","wikidata":"https://www.wikidata.org/wiki/Q624380","display_name":"Descent (aeronautics)","level":2,"score":0.7306036353111267},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.6370810866355896},{"id":"https://openalex.org/C68720959","wikidata":"https://www.wikidata.org/wiki/Q3527250","display_name":"Hadamard three-lines theorem","level":4,"score":0.626429557800293},{"id":"https://openalex.org/C6497535","wikidata":"https://www.wikidata.org/wiki/Q5156556","display_name":"Complex Hadamard matrix","level":4,"score":0.5781204700469971},{"id":"https://openalex.org/C2778112365","wikidata":"https://www.wikidata.org/wiki/Q3511065","display_name":"Sequence (biology)","level":2,"score":0.5485520958900452},{"id":"https://openalex.org/C9652623","wikidata":"https://www.wikidata.org/wiki/Q190109","display_name":"Field (mathematics)","level":2,"score":0.5158268809318542},{"id":"https://openalex.org/C114614502","wikidata":"https://www.wikidata.org/wiki/Q76592","display_name":"Combinatorics","level":1,"score":0.48223456740379333},{"id":"https://openalex.org/C121334634","wikidata":"https://www.wikidata.org/wiki/Q5637579","display_name":"Hadamard's maximal determinant problem","level":5,"score":0.4611665606498718},{"id":"https://openalex.org/C106487976","wikidata":"https://www.wikidata.org/wiki/Q685816","display_name":"Matrix (chemical analysis)","level":2,"score":0.424307644367218},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.3416176736354828},{"id":"https://openalex.org/C118615104","wikidata":"https://www.wikidata.org/wiki/Q121416","display_name":"Discrete mathematics","level":1,"score":0.3319091498851776},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.09181344509124756},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.07854732871055603},{"id":"https://openalex.org/C153294291","wikidata":"https://www.wikidata.org/wiki/Q25261","display_name":"Meteorology","level":1,"score":0.0},{"id":"https://openalex.org/C159985019","wikidata":"https://www.wikidata.org/wiki/Q181790","display_name":"Composite material","level":1,"score":0.0},{"id":"https://openalex.org/C54355233","wikidata":"https://www.wikidata.org/wiki/Q7162","display_name":"Genetics","level":1,"score":0.0},{"id":"https://openalex.org/C86803240","wikidata":"https://www.wikidata.org/wiki/Q420","display_name":"Biology","level":0,"score":0.0},{"id":"https://openalex.org/C192562407","wikidata":"https://www.wikidata.org/wiki/Q228736","display_name":"Materials science","level":0,"score":0.0}],"mesh":[],"locations_count":3,"locations":[{"id":"doi:10.1007/s10623-011-9493-1","is_oa":false,"landing_page_url":"https://doi.org/10.1007/s10623-011-9493-1","pdf_url":null,"source":{"id":"https://openalex.org/S81616010","display_name":"Designs Codes and Cryptography","issn_l":"0925-1022","issn":["0925-1022","1573-7586"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319965","host_organization_name":"Springer Nature","host_organization_lineage":["https://openalex.org/P4310319965"],"host_organization_lineage_names":["Springer Nature"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Designs, Codes and Cryptography","raw_type":"journal-article"},{"id":"pmh:oai:scholarbank.nus.edu.sg:10635/103606","is_oa":false,"landing_page_url":"http://scholarbank.nus.edu.sg/handle/10635/103606","pdf_url":null,"source":{"id":"https://openalex.org/S7407052290","display_name":"National University of Singapore","issn_l":null,"issn":[],"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":null,"host_organization_name":null,"host_organization_lineage":[],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"Scopus","raw_type":"Article"},{"id":"pmh:oai:dr.ntu.edu.sg:10356/97694","is_oa":false,"landing_page_url":"https://hdl.handle.net/10356/97694","pdf_url":null,"source":{"id":"https://openalex.org/S4306402609","display_name":"DR-NTU (Nanyang Technological University)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I172675005","host_organization_name":"Nanyang Technological University","host_organization_lineage":["https://openalex.org/I172675005"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Journal Article"}],"best_oa_location":null,"sustainable_development_goals":[{"display_name":"Reduced inequalities","id":"https://metadata.un.org/sdg/10","score":0.5600000023841858}],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":16,"referenced_works":["https://openalex.org/W564046778","https://openalex.org/W1520303766","https://openalex.org/W1566828525","https://openalex.org/W1612462974","https://openalex.org/W2012641766","https://openalex.org/W2028825982","https://openalex.org/W2029700997","https://openalex.org/W2058754382","https://openalex.org/W2059196145","https://openalex.org/W2065609889","https://openalex.org/W2097099020","https://openalex.org/W2260163155","https://openalex.org/W2611298788","https://openalex.org/W2732631235","https://openalex.org/W4243285511","https://openalex.org/W4285719527"],"related_works":["https://openalex.org/W1976224891","https://openalex.org/W2138472192","https://openalex.org/W4226106482","https://openalex.org/W1971692815","https://openalex.org/W4313302755","https://openalex.org/W3154819821","https://openalex.org/W2796326658","https://openalex.org/W3124308887","https://openalex.org/W2943994684","https://openalex.org/W1014943504"],"abstract_inverted_index":null,"counts_by_year":[{"year":2024,"cited_by_count":1},{"year":2022,"cited_by_count":2},{"year":2021,"cited_by_count":2},{"year":2020,"cited_by_count":1},{"year":2019,"cited_by_count":3},{"year":2018,"cited_by_count":2},{"year":2017,"cited_by_count":1},{"year":2016,"cited_by_count":5},{"year":2015,"cited_by_count":5},{"year":2014,"cited_by_count":8},{"year":2013,"cited_by_count":7},{"year":2012,"cited_by_count":3}],"updated_date":"2026-04-04T16:13:02.066488","created_date":"2025-10-10T00:00:00"}