Expand[CD[%,la,lb,lc,ld,le,lf]]

Out[24]=

                      p                        p                       p
  -(sigma      sigma     )   sigma      sigma        sigma      sigma
         ;pdef      ;a bc         ;pcef      ;a bd        ;pcdf      ;a be
  ------------------------ - --------------------- - --------------------- - 
             2                         2                       2
   
                      p                       p                       p
    sigma      sigma        sigma      sigma        sigma      sigma
         ;pcde      ;a bf        ;pbef      ;a cd        ;pbdf      ;a ce
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                      p                       p                       p
    sigma      sigma        sigma      sigma        sigma      sigma
         ;pbde      ;a cf        ;pbcf      ;a de        ;pbce      ;a df
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                      p                       p                       p
    sigma      sigma        sigma      sigma        sigma      sigma
         ;pbcd      ;a ef        ;paef      ;b cd        ;padf      ;b ce
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                      p                       p                       p
    sigma      sigma        sigma      sigma        sigma      sigma
         ;pade      ;b cf        ;pacf      ;b de        ;pace      ;b df
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                      p                       p                       p
    sigma      sigma        sigma      sigma        sigma      sigma
         ;pacd      ;b ef        ;pabf      ;c de        ;pabe      ;c df
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                      p                       p            p
    sigma      sigma        sigma      sigma        sigma     sigma
         ;pabd      ;c ef        ;pabc      ;d ef        ;e f      ;pabcd
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;d f      ;pabce        ;d e      ;pabcf        ;c f      ;pabde
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;c e      ;pabdf        ;c d      ;pabef        ;b f      ;pacde
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;b e      ;pacdf        ;b d      ;pacef        ;b c      ;padef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;a f      ;pbcde        ;a e      ;pbcdf        ;a d      ;pbcef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                                 p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;a c      ;pbdef        ;a b      ;pcdef        ;pef      ;a bcd
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                     p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;pdf      ;a bce        ;pde      ;a bcf        ;pcf      ;a bde
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                     p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;pce      ;a bdf        ;pcd      ;a bef        ;pbf      ;a cde
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                     p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;pbe      ;a cdf        ;pbd      ;a cef        ;pbc      ;a def
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                     p                       p                       p
    sigma     sigma         sigma     sigma         sigma     sigma
         ;paf      ;b cde        ;pae      ;b cdf        ;pad      ;b cef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                     p                       p             p
    sigma     sigma         sigma     sigma         sigma    sigma
         ;pac      ;b def        ;pab      ;c def        ;f       ;pabcde
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p                       p
    sigma    sigma          sigma    sigma          sigma    sigma
         ;e       ;pabcdf        ;d       ;pabcef        ;c       ;pabdef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
           p                       p
    sigma    sigma          sigma    sigma
         ;b       ;pacdef        ;a       ;pbcdef
    --------------------- - --------------------- + sigma        - 
              2                       2                  ;abcdef
   
                    p                       p                       p
    sigma    sigma          sigma    sigma          sigma    sigma
         ;pf      ;a bcde        ;pe      ;a bcdf        ;pd      ;a bcef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
                    p                       p                       p
    sigma    sigma          sigma    sigma          sigma    sigma
         ;pc      ;a bdef        ;pb      ;a cdef        ;pa      ;b cdef
    --------------------- - --------------------- - --------------------- - 
              2                       2                       2
   
          p                                p
    sigma   sigma           sigma   sigma
         ;       ;pabcdef        ;p      ;a bcdef
    --------------------- - ---------------------
              2                       2

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