Page 335 - Determinants and Their Applications in Mathematical Physics
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320   Appendix

          The polynomial
                                        m
                                            m
                              ψ mn (x)=         α n+r x r
                                            r
                                       r=0
          satisfies the relations
                                     ψ     = mψ m−1,n+1 ,
                                      mn
                            ψ mn − ψ m−1,n = xψ
                                              mn
                                          = mxψ m−1,n+1 .

          Exercises

          1. Prove that
                                       m
                                           m
                           φ m (x − h)=        (−h) φ m−r (x)
                                                    r
                                            r
                                       r=0
                                    =∆ φ 0 .
                                        m
                                        h
          2. If

                                S m (x)=      φ r φ s ,
                                        r+s=m

                                T m (x)=        φ r φ s φ t ,
                                        r+s+t=m
             prove that
                                S     =(m +1)S m−1 ,
                                  m
                                       m
                                           m +1
                          S m (x + h)=            h S m−r (x),
                                                   r
                                             r
                                      r=0
                                 T     =(m +2)T m−1 ,
                                  m
                                       m
                                           m +2

                          T m (x + h)=            h T m−r (x).
                                                   r
                                             r
                                      r=0
          3. Prove that
                                          ∞
                                       1
                                 −1
                               φ   =        (−1) c mn x ,
                                                n
                                                      n
                                 m
                                         n=0
                                      α m
             where
                     c m0 =1,

                                      m
                            1
                     c mn =                               ,  n ≥ 1.
                           α n    m − i + j − 1  α m−i+j−1
                            m                           n
             This determinant is of Hessenberg form, is symmetric about its sec-
             ondary diagonal, and contains no more than (m + 1) nonzero diagonals
             parallel to and including the principal diagonal.
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