Page 337 - Determinants and Their Applications in Mathematical Physics
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322   Appendix

          Differential equation.

                         xL (x)+(1 − x)L (x)+ nL n (x)=0;

                            n             n
          Appell relation. If

                                               1
                                                  ,
                                          n
                                               x
                                 φ n (x)= x L n
          then

                                  φ (x)= nφ n−1 (x).
                                   n
          φ n (x) is the Laguerre polynomial with its coefficients arranged in reverse
          order.

          Hermite Polynomial H n (x)
          Definition.

                                 N
                                        r
                                    (−1) (2x) n−2r         1
                      H n (x)= n!                ,  N =   2 n .
                                     r!(n − 2r)!
                                 r=0
          Rodrigues formula.
                                       2       2         d
                        H n (x)=(−1) e D  n  e −x  ,  D =  ;
                                    n x
                                                        dx
          Generating function relation.
                                         ∞
                                     2      H n (x)t n
                                e 2xt−t  =          ;
                                               n!
                                        n=0
          Recurrence relation.
                         H n+1 (x) − 2xH n (x)+2nH n−1 (x)=0;
          Differential equation.


                           H (x) − 2xH (x)+2nH n (x)=0;
                             n         n
          Appell relation.

                                 H (x)=2nH n−1 (x).
                                  n
          Legendre Polynomials P n (x)

          Definition.
                           1     (−1) (2n − 2r)! x n−2r       1
                              N
                                     r
                   P n (x)=                          ,  N =  2 n .
                           2 n    r!(n − r)! (n − 2r)!
                              r=0
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