caa a22 4500 467931895 CHVBK 20180406152945.0 cr unu---uuuuu 170328e20061201xx s 000 0 eng 10.1007/s00020-006-1436-2 doi (NATIONALLICENCE)springer-10.1007/s00020-006-1436-2 Exner George Department of Mathematics, Bucknell University, 17837, Lewisburg, PA, U.S.A aut On n -contractive and n -hypercontractive Operators [Elektronische Daten] [George Exner] Abstract.: We consider in this paper the classes of n-hypercontractive Hilbert space operators, primarily weighted shifts, and obtain results for back step extensions of recursively generated subnormal weighted shifts and for perturbations in the first weight of the Bergman shift. We compare the results with those for the classes of k-hyponormal operators, and recapture, by an n-hypercontractive approach, a subnormality result originally proved in the k-hyponormal context. Birkhäuser Verlag, Basel, 2006 n -contractive nationallicence n -hypercontractive nationallicence weighted shift nationallicence back step extension nationallicence k -hyponormal nationallicence Integral Equations and Operator Theory Birkhäuser-Verlag; http://www.birkhauser.ch 56/4(2006-12-01), 451-468 0378-620X 56:4<451 2006 56 20 https://doi.org/10.1007/s00020-006-1436-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00020-006-1436-2 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Exner George Department of Mathematics, Bucknell University, 17837, Lewisburg, PA, U.S.A aut NATIONALLICENCE 773 0- Integral Equations and Operator Theory Birkhäuser-Verlag; http://www.birkhauser.ch 56/4(2006-12-01), 451-468 0378-620X 56:4<451 2006 56 20 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 457590831 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer