{"id":"https://openalex.org/W2047808405","doi":"https://doi.org/10.1016/0890-5401(89)90063-1","title":"Enumerative counting is hard","display_name":"Enumerative counting is hard","publication_year":1989,"publication_date":"1989-07-01","ids":{"openalex":"https://openalex.org/W2047808405","doi":"https://doi.org/10.1016/0890-5401(89)90063-1","mag":"2047808405"},"language":"en","primary_location":{"id":"doi:10.1016/0890-5401(89)90063-1","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0890-5401(89)90063-1","pdf_url":null,"source":{"id":"https://openalex.org/S59933527","display_name":"Information and Computation","issn_l":"0890-5401","issn":["0890-5401","1090-2651"],"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":"Information and Computation","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/A5101599971","display_name":"Jin\u2010Yi Cai","orcid":"https://orcid.org/0009-0003-0675-6060"},"institutions":[{"id":"https://openalex.org/I32971472","display_name":"Yale University","ror":"https://ror.org/03v76x132","country_code":"US","type":"education","lineage":["https://openalex.org/I32971472"]}],"countries":["US"],"is_corresponding":false,"raw_author_name":"Jin-Yi Cai","raw_affiliation_strings":["Department of Computer Science, Yale University, New Haven, Connecticut 06520, USA"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Computer Science, Yale University, New Haven, Connecticut 06520, USA","institution_ids":["https://openalex.org/I32971472"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5113502191","display_name":"Lane A. Hemachandra","orcid":null},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Lane A. Hemachandra","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":{"value":2840,"currency":"USD","value_usd":2840},"apc_paid":null,"fwci":3.3397,"has_fulltext":false,"cited_by_count":62,"citation_normalized_percentile":{"value":0.93270588,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":89,"max":96},"biblio":{"volume":"82","issue":"1","first_page":"34","last_page":"44"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10720","display_name":"Complexity and Algorithms in Graphs","score":0.9998999834060669,"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/T10720","display_name":"Complexity and Algorithms in Graphs","score":0.9998999834060669,"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/T12002","display_name":"Computability, Logic, AI Algorithms","score":0.9988999962806702,"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/T12072","display_name":"Machine Learning and Algorithms","score":0.9984999895095825,"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"}}],"keywords":[{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.5400415658950806},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.3476448059082031}],"concepts":[{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.5400415658950806},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.3476448059082031}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1016/0890-5401(89)90063-1","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0890-5401(89)90063-1","pdf_url":null,"source":{"id":"https://openalex.org/S59933527","display_name":"Information and Computation","issn_l":"0890-5401","issn":["0890-5401","1090-2651"],"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":"Information and Computation","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":35,"referenced_works":["https://openalex.org/W1485836178","https://openalex.org/W1552288906","https://openalex.org/W1553952730","https://openalex.org/W1565875822","https://openalex.org/W2002385864","https://openalex.org/W2006912660","https://openalex.org/W2014603110","https://openalex.org/W2020831804","https://openalex.org/W2036265926","https://openalex.org/W2041943346","https://openalex.org/W2044504659","https://openalex.org/W2045924252","https://openalex.org/W2053094807","https://openalex.org/W2059442002","https://openalex.org/W2060270693","https://openalex.org/W2070678975","https://openalex.org/W2085634981","https://openalex.org/W2111824166","https://openalex.org/W2115826669","https://openalex.org/W2153191867","https://openalex.org/W2165293955","https://openalex.org/W2281668463","https://openalex.org/W2737885910","https://openalex.org/W2912736906","https://openalex.org/W2913222977","https://openalex.org/W4210277052","https://openalex.org/W6628822037","https://openalex.org/W6633136800","https://openalex.org/W6633148477","https://openalex.org/W6633842933","https://openalex.org/W6659573362","https://openalex.org/W6661988143","https://openalex.org/W6668336749","https://openalex.org/W6674913671","https://openalex.org/W6858827895"],"related_works":["https://openalex.org/W2899084033","https://openalex.org/W2748952813","https://openalex.org/W1979597421","https://openalex.org/W2007980826","https://openalex.org/W4245490552","https://openalex.org/W4225152035","https://openalex.org/W2061531152","https://openalex.org/W3002753104","https://openalex.org/W2077600819","https://openalex.org/W1587224694"],"abstract_inverted_index":null,"counts_by_year":[{"year":2020,"cited_by_count":2},{"year":2013,"cited_by_count":1}],"updated_date":"2026-08-21T09:56:20.448147","created_date":"2025-10-10T00:00:00"}