000084209 001__ 84209 000084209 005__ 20200513005823.0 000084209 0247_ $$2doi$$a10.1016/j.cam.2018.09.029 000084209 0248_ $$2sideral$$a108573 000084209 037__ $$aART-2018-108573 000084209 041__ $$aeng 000084209 100__ $$aAlonso, P. 000084209 245__ $$aCombined matrices of almost strictly sign regular matrices 000084209 260__ $$c2018 000084209 5060_ $$aAccess copy available to the general public$$fUnrestricted 000084209 5203_ $$aThe combined matrix is a very useful concept for many applications. Almost strictly sign regular (ASSR) matrices form an important structured class of matrices with two possible zero patterns, which are either type-I staircase or type-II staircase. We prove that, under an irreducibility condition, the pattern of zero and nonzero entries of an ASSR matrix is preserved by the corresponding combined matrix. Without the irreducibility condition, it is proved that type-I and type-II staircases are still preserved. Illustrative numerical examples are included. 000084209 536__ $$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/MTM2015-65433-P$$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/MTM2017-90682-REDT$$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/TIN2017-87600-P 000084209 540__ $$9info:eu-repo/semantics/openAccess$$aby-nc-nd$$uhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/ 000084209 590__ $$a1.883$$b2018 000084209 591__ $$aMATHEMATICS, APPLIED$$b47 / 254 = 0.185$$c2018$$dQ1$$eT1 000084209 592__ $$a0.849$$b2018 000084209 593__ $$aComputational Mathematics$$c2018$$dQ2 000084209 593__ $$aApplied Mathematics$$c2018$$dQ2 000084209 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/acceptedVersion 000084209 700__ $$0(orcid)0000-0002-1340-0666$$aPeña, J.M.$$uUniversidad de Zaragoza 000084209 700__ $$aSerrano, M.L. 000084209 7102_ $$12005$$2595$$aUniversidad de Zaragoza$$bDpto. Matemática Aplicada$$cÁrea Matemática Aplicada 000084209 773__ $$g354 (2018), 144 - 151$$pJ. comput. appl. math.$$tJournal of Computational and Applied Mathematics$$x0377-0427 000084209 8564_ $$s189914$$uhttps://zaguan.unizar.es/record/84209/files/texto_completo.pdf$$yPostprint 000084209 8564_ $$s439698$$uhttps://zaguan.unizar.es/record/84209/files/texto_completo.jpg?subformat=icon$$xicon$$yPostprint 000084209 909CO $$ooai:zaguan.unizar.es:84209$$particulos$$pdriver 000084209 951__ $$a2020-05-13-00:50:35 000084209 980__ $$aARTICLE