[Authors]
 V. N. Malozemov, M. F. Monaco, A. V. Petrov

[Title]
 Frobenius and Sherman-Morrison formulas and related topics

[AMS Subj-class]
 15A09  Matrix inversion, generalized inverses 
       
[Abstract]
 The problem of bordering of a singular matrix in order to obtain
 a nonsingular matrix is considered. The minimal width of the bordering
 band is determined. In case of the minimal width, the invertibility
 criterion is established. The numerical method of inversion of
 a bordered matrix is described in case when the initial matrix is
 singular.

[Comments]
 9 pp., Russian

[Contact e-mail]
 malv@gamma.math.spbu.ru