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The semigroup <jats:inline-formula><jats:alternatives><jats:tex-math>$${{\\,\\textrm{F}\\,}}(X)$$<\/jats:tex-math><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                  <mml:mrow>\n                    <mml:mrow>\n                      <mml:mspace\/>\n                      <mml:mtext>F<\/mml:mtext>\n                      <mml:mspace\/>\n                    <\/mml:mrow>\n                    <mml:mo>(<\/mml:mo>\n                    <mml:mi>X<\/mml:mi>\n                    <mml:mo>)<\/mml:mo>\n                  <\/mml:mrow>\n                <\/mml:math><\/jats:alternatives><\/jats:inline-formula> is introduced by a presentation and the word problem for that presentation is solved. The structure of the semigroup <jats:inline-formula><jats:alternatives><jats:tex-math>$${{\\,\\textrm{F}\\,}}(X)$$<\/jats:tex-math><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                  <mml:mrow>\n                    <mml:mrow>\n                      <mml:mspace\/>\n                      <mml:mtext>F<\/mml:mtext>\n                      <mml:mspace\/>\n                    <\/mml:mrow>\n                    <mml:mo>(<\/mml:mo>\n                    <mml:mi>X<\/mml:mi>\n                    <mml:mo>)<\/mml:mo>\n                  <\/mml:mrow>\n                <\/mml:math><\/jats:alternatives><\/jats:inline-formula> is also studied.<\/jats:p>","DOI":"10.1007\/s00233-024-10475-1","type":"journal-article","created":{"date-parts":[[2024,10,7]],"date-time":"2024-10-07T16:01:44Z","timestamp":1728316904000},"page":"639-668","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Regular semigroups weakly generated by set"],"prefix":"10.1007","volume":"109","author":[{"given":"Lu\u00eds","family":"Oliveira","sequence":"first","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2024,10,7]]},"reference":[{"key":"10475_CR1","doi-asserted-by":"publisher","first-page":"630","DOI":"10.1006\/jabr.1994.1169","volume":"166","author":"K Auinger","year":"1994","unstructured":"Auinger, K.: The bifree locally inverse semigroup on a set. 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