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A simple method is described, for calculation of character table
for the symmetry groups of molecules consisting of a number XH$_3$
groups attached to a rigid framework. For the full non-rigid group
(f-NRG) of the trimethylamine-BH$_3$ Addend, with $C_{3v}$
symmetry, we prove that it is a group of order 1944 with 27
conjugacy classes. The character tables of this group are
calculated.
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