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[Davide Sangalli <davide.sangalli@gmail.com>]

Dear forum,
I've a question on symmetries.
I'm running abinit on some cnt and in particular the (5,5) and the (8,8)

********************************************************
For the (5,5) in the log files abinit says:
 symanal : COMMENT -
  The Bravais lattice determined only from the primitive
  vectors, bravais(1)=  6, is more symmetric
  than the real one, iholohedry=  2, obtained by taking into
  account the atomic positions.
 symspgr : the symmetry operation no.   1 is the identity
 symspgr : the symmetry operation no.   2 is an inversion
 symaxes : the symmetry operation no.   3 is a 2_1-axis
 symplanes : the symmetry operation no.   4 is a mirror plane
 symspgr : spgroup=  11  P2_1/m   (=C2h^2)

but then reports 2 symmetries in the report file:
 symmorphi         0
    symrel    1  0  0   0  1  0   0  0  1       1  0  0   0  1  0   0  0 -1
    toldfe    1.00000000E-06 Hartree
***************************************************************

On the other hand for the (8,8) in the log abinit says:
 symanal : COMMENT -
  The Bravais lattice determined only from the primitive
  vectors, bravais(1)=  6, is more symmetric
  than the real one, iholohedry=  2, obtained by taking into
  account the atomic positions.
 symspgr : the symmetry operation no.   1 is the identity
 symspgr : the symmetry operation no.   2 is an inversion
 symaxes : the symmetry operation no.   3 is a 2-axis
 symplanes : the symmetry operation no.   4 is a mirror plane
 symspgr : spgroup=  10  P2/m   (=C2h^1)

and then reports 4 symmetries in the report file:
 symmorphi         0
    symrel    1  0  0   0  1  0   0  0  1      -1  0  0   0 -1  0   0  0 -1
             -1  0  0   0 -1  0   0  0  1       1  0  0   0  1  0   0  0 -1
    toldfe    1.00000000E-06 Hartree
******************************************************************

I do not understand what is going on. 
Shouldn't there be 4 symmetries in both ?

Regards,
Davide