{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T21:18:36Z","timestamp":1786051116662,"version":"3.56.0"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,13]],"date-time":"2019-02-13T00:00:00Z","timestamp":1550016000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2016R1D1A1A09916450"],"award-info":[{"award-number":["2016R1D1A1A09916450"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The present paper aims to establish the first order differential subordination relations between functions with a positive real part and starlike functions related to the Bell numbers. In addition, several sharp radii estimates for functions in the class of starlike functions associated with the Bell numbers are determined.<\/jats:p>","DOI":"10.3390\/sym11020219","type":"journal-article","created":{"date-parts":[[2019,2,14]],"date-time":"2019-02-14T03:21:46Z","timestamp":1550114506000},"page":"219","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Starlike Functions Related to the Bell Numbers"],"prefix":"10.3390","volume":"11","author":[{"given":"Nak Eun","family":"Cho","sequence":"first","affiliation":[{"name":"Department of Applied Mathematics, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sushil","family":"Kumar","sequence":"additional","affiliation":[{"name":"Bharati Vidyapeeth\u2019s College of Engineering, Delhi 110063, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7929-7158","authenticated-orcid":false,"given":"Virendra","family":"Kumar","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Ramanujan College, University of Delhi, Kalkaji, New Delhi 110019, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3632-7529","authenticated-orcid":false,"given":"V.","family":"Ravichandran","sequence":"additional","affiliation":[{"name":"Department of Mathematics, National Institute of Technology, Tiruchirappalli, Tamil Nadu 620015, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9277-8092","authenticated-orcid":false,"given":"H. M.","family":"Srivastava","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics, University of Victoria, Victoria, BC V8W 3R4, Canada"},{"name":"Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,13]]},"reference":[{"key":"ref_1","unstructured":"Ma, W.C., and Minda, D. (1992, January 19\u201323). A unified treatment of some special classes of univalent functions. Proceedings of the Conference on Complex Analysis, Tianjin, China."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"159","DOI":"10.4064\/ap-23-2-159-177","article-title":"Extremal problems for a family of functions with positive real part and for some related families","volume":"23","author":"Janowski","year":"1970","journal-title":"Ann. Polon. 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