FUNCTION:  partitions[overptnrank] - overpartition rank
 
CALLING SEQUENCE:  overptnrank(optn)
 
PARAMETERS:    optn - LIST [dptn, ptn]
                      where dptn is a partition into distinct parts
                      and ptn is a partition 
 
SYNOPSIS:  
  overptnrank(optn) returns the overpartition rank of the 
  of the overpartition optn
 
EXAMPLES:  
                    
> with(combinat):
> with(partitions):
> with(orank):
> RT4:=[seq(overptnrank(overptns(4)[k]),k=1..14)];
            RT4 := [-3, -1, 0, 1, 3, -3, -1, 1, -1, 0, -1, 1, 1, 3]

> seq(nops(select(x->if x=k then true else false fi,RT4)),k=-4..4);
                           0, 2, 0, 4, 2, 4, 0, 2, 0

> seq(NBAR(abs(k),4),k=-4..4);
                           0, 2, 0, 4, 2, 4, 0, 2, 0

DISCUSSION:  
We calculated the 14 overpartitions of 4 and their
   overpartition ranks. We also confirmed the values
   of NBAR(m,n) for n = 4.
   NBAR(m,n) = number of overpartitions of n with overpartition rank m
                    
SEE ALSO:  overptns, overptncrank