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4.11 Hankelians 4  141

          The only element which remains in column n is a 1 in position (n +1,n).
          Hence,

                        h 11      h 12   ···    h 1,n−1      v n1 /n


                        h 21      h 22   ···    h 2,n−1
                                                                        .
                                                           v n2 /(n +1)
            E n+1 = −
                       .....................................................
                      (h n1 − t)(h n2 − t)  ··· (h n,n−1 − t)  v nn /(2n − 1)

                                                                      n
                                                                   (4.11.20)
          It is seen from (4.11.3) (with i = n) that the sum of the elements in the
          last column is unity and it is seen from the lemma that the sum of the
          elements in column j is x 2j−1 ,1 ≤ j ≤ n − 1. Hence, after performing the
          row operation
                                           n

                                    R =      R i ,                 (4.11.21)

                                      n
                                          i=1
          the result is

                    h 11    h 12  ···   h 1,n−1      v n1 /n

                    h 21    h 22  ···   h 2,n−1   v n2 /(n +1)
           E n+1 =   ................................................   . (4.11.22)



                    h n−1,1  h n−1,2  ··· h n−1,n−1  v n,n−1 /(2n − 2)
                     x       x    ···   x              1
                              3          2n−3
                                                               n
          The final set of column operations is
                         C = C j − x 2j−1 C n ,  1 ≤ j ≤ n − 1,    (4.11.23)

                           j
          which removes the x’s from the last row. The result can then be expressed
          in the form
                                             (n) ∗
                                 E n+1 = − h      ,                (4.11.24)

                                               n−1
                                           ij
          where, referring to (4.11.5),
                        (n) ∗  (n)   v ni x 2j−1
                       h    = h   −
                                    n + i − 1
                        ij     ij

                                           1         1
                                  2j−1
                            = v ni x            −           + δ ij t
                                        i + j − 1  i + n − 1
                              	         
	         2j−1
                                           (n − j)x
                            =      v ni                  + δ ij t
                                i + n − 1    i + j − 1
                                	      
	         2j−1
                                           (n − j)x
                            = −   v n−1,i               + δ ij t
                                  n − i     i + j − 1
                                	      
	       2j−1
                                  n − j   v n−1,i x
                            = −                      − δ ij t
                                  n − i    i + j − 1

                                  n − j   (n−1)
                                        h
                            = −         ¯     ,
                                  n − i   ij
                      (n) ∗       ¯  (n−1)

                     h      = − −h         .                       (4.11.25)
                        n−1             n−1
                     ij            ij
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