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      SUBROUTINE LUELMP (A,B,N,X,m)                                       

!C                                                                       

        DIMENSION          A(m),B(n),X(n)

!DIMENSION          A(n*(n-1)/2),B(n),X(n)                                 

      DOUBLE PRECISION   A,B,X,T,ZERO                                   

      DATA               ZERO/0.0D0/                                    

!C                                  FIRST EXECUTABLE STATEMENT           

!C                                  SOLUTION OF LY = B                   

      IP=1                                                              

      IW = 0                                                            

      DO 15 I=1,N                                                       

         T=B(I)                                                         

         IM1 = I-1                                                      

         IF (IW .EQ. 0) GO TO 9                                         

         IP=IP+IW-1                                                     

         DO 5 K=IW,IM1                                                  

            T = T-A(IP)*X(K)                                            

            IP=IP+1                                                     

    5    CONTINUE                                                       

         GO TO 10                                                       

    9    IF (T .NE. ZERO) IW = I                                        

         IP = IP+IM1                                                    

   10    X(I)=T*A(IP)                                                   

         IP=IP+1                                                        

   15 CONTINUE                                                          

!C                                  SOLUTION OF UX = Y                   

      N1 = N+1                                                          

      DO 30 I = 1,N                                                     

         II = N1-I                                                      

         IP=IP-1                                                        

         IS=IP                                                          

         IQ=II+1                                                        

         T=X(II)                                                        

         IF (N.LT.IQ) GO TO 25                                          

         KK = N                                                         

         DO 20 K=IQ,N                                                   

            T = T - A(IS) * X(KK)                                       

            KK = KK-1                                                   

            IS = IS-KK                                                  

   20    CONTINUE                                                       

   25    X(II)=T*A(IS)                                                  

   30 CONTINUE                                                          

      RETURN                                                            

      END