Page 170 - Determinants and Their Applications in Mathematical Physics
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4.12 Hankelians 5  155
                                      2
                             1   ,  (ζ − 1) n
                        =                    dζ     (put ζ = x +2t)
                          2 n+1 πi  (ζ − x) n+1
                                  C
                             1   ,  [(x +1+2t)(x − 1+2t)] n
                        =                                   dt
                          2 n+1 πi  C       (2t) n+1
                           1  ,  g(t)
                        =             dt
                          2πi  C   t n+1
                          g (n) (0)
                        =       ,
                            n!
          where
                               - 1         .- 1         .  n
                        g(t)=    (x +1)+ t     (x − 1) + t  .       (4.12.5)
                                2            2
          The lemma follows.


                                        n
                                     n
                                            n    n
                                                             t
                                                         v
                   [(u + t)(v + t)] =                u n−r n−s r+s
                                n
                                            r    s
                                    r=0 s=0
                                    2n

                                  =    λ np t p
                                    p=0
          where
                       p
                          n      n

                λ np =                u n−s n−p+s ,  0 ≤ p ≤ 2n,    (4.12.6)
                                          v
                           s    p − s
                      s=0
          which, by symmetry, is unaltered by interchanging u and v.
            In particular,
                λ 00 =1,  λ n0 =(uv) ,  λ n,2n =1,  λ nn = P n (x).  (4.12.7)
                                   n
          Lemma 4.57.
          a. λ i,i−r =(uv) λ i,i+r ,
                        r
          b. λ i,i−r λ j,j+r = λ i,i+r λ j,j−r .
          Proof.
                                n+r
                                     n       n
                                                        v
                       λ n,n+r =                    u n−s s−r
                                     s    n + r − s
                                s=0
                                n+r
                                     n      n

                              =                  u n−s s−r .
                                                     v
                                     s    s − r
                                s=r
          Changing the sign of r,
                         n−r
                               n     n
                λ n,n−r =                 u n−s s+r   (put s = n − σ)
                                              v
                               s    s + r
                        s=−r
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