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174   5. Further Determinant Theory

          5.1.3  Orthogonal Polynomials
          Determinants which represent orthogonal polynomials (Appendix A.5)
          have been constructed using various methods by Pandres, R¨osler, Yahya,
          Stein et al., Schleusner, and Singhal, Frost and Sackfield and others. The
          following method applies the Rodrigues formulas for the polynomials.
            Let
                                     A n = |a ij | n ,

          where

                     j − 1   (j−i)   j − 1  (j−i+1)   (r)
              a ij =       u     −         v      ,  u   = D (u), etc.,
                                                             r
                     i − 1           i − 2
                   vy

               u =     = v(log y) .                                  (5.1.9)
                    y
          In some detail,
                 u     u       u        u       ··· u (n−2)   u (n−1)

                 −v  u − v    2u − v      3u − v      ···  ···  ···



                      −v     u − 2v  3u − 3v    ···  ···        ···


                              −v      u − 3v    ···  ···        ···      .

          A n =
                                        −v      ···  ···        ···



                                              ............................
                                                     −v    u − (n − 1)v

                                                                        n
                                                                    (5.1.10)
          Theorem.
              (n+1)
          a. A     = −A ,

                        n
              n+1,n
                  v D (y)
                      n
                   n
          b. A n =        .
                     y
          Proof. Express A n in column vector notation:

                              A n = C 1 C 2 C 3 ··· C n ,


                                                    n
          where

                                                         T
                         C j = a 1j a 2j a 3j ··· a j+1,j O n−j−1   (5.1.11)
                                                         n
          where O r represents an unbroken sequence of r zero elements.
            Let C denote the column vector obtained by dislocating the elements
                 ∗
                 j
          of C j one position downward, leaving the uppermost position occupied by
          a zero element:

                          ∗                               T
                        C = Oa 1j a 2j ··· a jj a j+1,j O n−j−2  .  (5.1.12)
                          j
                                                          n
          Then,
                                                                         T

          C + C = a      (a    + a 1j )(a    + a 2j ) ··· (a    + a jj ) a j+1,j O n−j−2  .
                ∗
           j    j     1j  2j        3j          j+1,j
                                                                        n
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