An analogue of Fabry's theorem for generalized Pad\'e approximants
    
    
  
  
  
      
      
      
        
Sbornik. Mathematics, Tome 200 (2009) no. 7, pp. 981-1050
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			The current theory of Padé approximation emphasises results of an inverse character, when  conclusions about the properties of the approximated function are drawn from information about the behaviour of the approximants. In this paper Gonchar's conjecture is proved; it states that analogues of Fabry's classical ‘ratio’ theorem hold for rows of the table of Padé approximants for orthogonal expansions, multipoint Padé approximants and Padé-Faber approximants. These are the most natural generalizations of the construction of classical Padé approximants. For these Gonchar's conjecture has already been proved by Suetin. The proof presented here is based, on the one hand, on Suetin's result and, on the other hand, on an extension of Poincaré's theorem  on recurrence relations with coefficients constant in the limit, which is obtained in the paper.
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Keywords: 
recurrence relations, Fabry's theorem, Faber polynomials.
Mots-clés : Padé approximants, orthogonal polynomials
                    
                  
                
                
                Mots-clés : Padé approximants, orthogonal polynomials
@article{SM_2009_200_7_a1,
     author = {V. I. Buslaev},
     title = {An analogue of {Fabry's} theorem for generalized {Pad\'e} approximants},
     journal = {Sbornik. Mathematics},
     pages = {981--1050},
     publisher = {mathdoc},
     volume = {200},
     number = {7},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2009_200_7_a1/}
}
                      
                      
                    V. I. Buslaev. An analogue of Fabry's theorem for generalized Pad\'e approximants. Sbornik. Mathematics, Tome 200 (2009) no. 7, pp. 981-1050. http://geodesic.mathdoc.fr/item/SM_2009_200_7_a1/
