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158   4. Particular Determinants

                      H n = |S i+j−2 | n = λ n x n(n+1)/2 ,
                       J n = |A i+j−2 | n = λ n x n(n−1)/2 ,
          where
                                                    2
                              λ n = 1! 2! 3! ··· (n − 1)!] .
            The following proofs differ from the originals in some respects.
          Proof. It is proved using a slightly different notation in Theorem 4.28
          in Section 4.8.5 on Turanians that
                                                    2
                               E n G n − E n+1 G n−1 = F ,
                                                   n
          which is equivalent to
                                                    2
                             E n−1 G n−1 − E n G n−2 = F n−1 .     (4.12.16)
          Put x = e in (4.12.5) so that
                  t
                                    −t
                              D x = e D t
                                                ∂
                              D t = xD x ,  D x =  , etc.          (4.12.17)
                                               ∂x
          Also, put
                                  θ m (t)= ψ m (e )
                                              t
                                          ∞

                                       =     r e
                                              m rt
                                          r=1
                                  θ (t)= θ m+1 (t).                (4.12.18)

                                   m
          Define the column vector C j (t) as follows:
                                                         T
                           C j (t)= θ j (t) θ j+1 (t) θ j+2 (t) ...
          so that

                                    C = C j+1 (t).                 (4.12.19)
                                     j
          The number of elements in C j is equal to the order of the determinant of
          which it is a part, that is, n, n − 1, or n − 2 in the present context.
            Let

                   Q n (t, τ)= C 0 (τ) C 1 (t) C 2 (t) ··· C n−1 (t) ,  (4.12.20)


                                                        n
          where the argument in the first column is τ and the argument in each of
          the other columns is t. Then,
                                    Q n (t, t)= E n .              (4.12.21)
          Differentiate Q n repeatedly with respect to τ, apply (4.12.19), and put
          τ = t.
                 D {Q n (t, t)} =0,  1 ≤ r ≤ n − 1,                (4.12.22)
                   r
                   τ
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