      function cgc2 (i1,i2,i3)
c *** see RH Landau, Program lpott, 1981
      Implicit  Real*8   (a-h,o-z)
      Dimension g(150)
c
        data n/1/
      If (n.ne.1) GoTo 20
      n = 2
      g(1) = log(1.)
      Do 10 i=2,110
c      removed card
         g(i) = log(i-1.)+g(i-1)
 10   Continue
 20   Continue
      If ((i1+i2+i3)/2*2.eq.(i1+i2+i3)) GoTo 30
      m1 = (i1+i2+i3-3)/2
      cgc2 = (2*i3-1)*exp(g(i1+i2-i3)+g(i2+i3-i1)+g(i3+i1-i2)-g(i1+i2+i3
     1-1)+2.*(g(m1+1)-g(m1-i1+2)-g(m1-i2+2)-g(m1-i3+2)))
      GoTo 40
 30   cgc2 = 0.0
 40   Return
      End
