Page 141 - Determinants and Their Applications in Mathematical Physics
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126   4. Particular Determinants

                        (−1) r+1 n(r + n − 1)!
                 r1
          4. a. K (0) =                    .
                          (r − 1)!r!(n − r)!
                 n

                        (−1) r+s rs  n − 1  n − 1    r + n − 1   s + n − 1
             b. K (0) =                                                   .
                 rs
                         r + s − 1
                 n                  r − 1   s − 1       r           s
                            [1!2!3! ··· (n − 1)!] 3
             c. K n (0) =                         .
                        n!(n + 1)!(n + 2)! ··· (2n − 1)!
          5.

                       1            1
                           =2  n
                       2         2i +2j − 1
                  K n
                                          n
                                                  n−1
                               2                2     (2r + 1)!(r + n)!
                           =2 2n  [1!2!3! ··· (n − 1)!]             .
                                                      r!(2r +2n + 1)!
                                                  r=0
             [Apply the Legendre duplication formula in Appendix A.1].
          6. By choosing h suitably, evaluate |1/(2i +2j − 3)| n .
            The next set of identities are of a different nature. The parameter n is
          omitted from V nr , K , and so forth.
                            ij
                            n
          Identities 2.
                         K  sj
                                 = δ rs ,  1 ≤ r ≤ n.              (4.10.16)
                     h + r + j − 1
                   j
                          V j
                                 =1,   1 ≤ r ≤ n.                  (4.10.17)
                     h + r + j − 1
                   j

                                                =  δ rs  ,  1 ≤ r, s ≤ n.(4.10.18)
                                 V j
                     (h + r + j − 1)(h + s + j − 1)
                   j                              V r
                         jK  1j
                                 = V 1 − hδ r1 ,  1 ≤ r ≤ n.       (4.10.19)
                     h + r + j − 1
                   j

                     V j =      K ij  = n(n + h).                  (4.10.20)
                   j       i  j
                              2
                     jK  1j  =(n + nh − h)V 1 .                    (4.10.21)
                   j
          Proof. Equation (4.10.16) is simply the identity

                                      k rj K  sj  = δ rs .
                                   j
          To prove (4.10.17), apply (4.10.9) with r → j and (4.10.4): and (4.10.12),
                                           (h + j)K j1
                   V 1       V j     =
                         h + r + j − 1     h + r + j − 1
                      j                 j

                                                   r − 1       j1
                                     =      1 −              K
                                               h + r + j − 1
                                        j
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