Page 149 - Determinants and Their Applications in Mathematical Physics
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134   4. Particular Determinants

            Let
                             A = |φ m | n ,  0 ≤ m ≤ 2n − 2,
          where
                                        x 2m+2  − 1
                                  φ m =          .
                                          m +1
          A is identical to |a ij | n , where a ij is defined in Theorem 4.41. Let Y denote
          the determinant of order (n + 1) obtained by bordering A by the row

                                   111 ... 1 •
                                              n+1
          below and the column
                                  1 1      1
                                                  T
                                1     ...      •
                                  3 5    2n − 1
                                                 n+1
          on the right.
          Theorem 4.42.
                                        n  2i−1
                                 n(n−1)     2  (n + i − 1)!
                      Y = −nK n φ                        φ n−i ,
                                 0          (n − i)!(2i)!  0
                                       i=1
          where K n is the simple Hilbert determinant.
          Proof. Perform the column operations

                                   C = C j − C j−1
                                    j
          in the order j = n, n − 1,n − 2,..., 2. The result is a determinant in which
          the only nonzero element in the last row is a 1 in position (n+1, 1). Hence,

                           ∆φ 0   ∆φ 1   ∆φ 2   ···  ∆φ n−2    1
                                                               1

                           ∆φ 1   ∆φ 2   ∆φ 3   ···  ∆φ n−1
                                                               3
                        n                                      1
               Y =(−1)   ∆φ 2     ∆φ 3   ∆φ 4   ···                 .
                                                               5
                                                      ∆φ n

                           ............................................
                                                               1

                          ∆φ n−1        ∆φ n+1  ··· ∆φ 2n−3
                                  ∆φ n
                                                             2n−1 n
          Perform the row operations

                                   R = R i − R i−1
                                    i
          in the order i = n, n − 1,n − 2,..., 2. The result is

                         ∆φ 0     ∆φ 1    ∆φ 2  ···  ∆φ n−2      1
                          2        2       2          2

                         ∆ φ 0    ∆ φ 1  ∆ φ 2  ···  ∆ φ n−1   ∆α 0
                          2        2       2           2
                     n
             Y =(−1)   ∆ φ 1      ∆ φ 2  ∆ φ 3  ···   ∆ φ n    ∆α 1   ,

                         ..................................................
                         2        2        2          2

                        ∆ φ n−2  ∆ φ n−1  ∆ φ n  ··· ∆ φ 2n−4  ∆α n−2 n
          where
                                            1
                                   α m =        .
                                         2m +1
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