Major index of skew-SYT
For a standard Young tableaux (SYT), I can compute the major index as follows:
T = Tableau([[1,2,3],[4,5]])
T.major_index()
Is there a way to compute the major index of a skew-SYT currently? Something like:
S = SkewTableaux().from_expr([[1,1],[[5],[3,4],[1,2]]])
S.major_index()
At the moment, it seems major_index() is not defined for the SkewTableau-class.
EDIT: The major index of a (skew) standard Young tableau T, denoted maj(T), is defined as follows. A descent of T is an entry i such that i+1 appears strictly below i in T. Define maj(T) as the sum of all descents of T. For example, the major index of the skew standard Young tableau above is 2+4=6.
FindStat has a definition, although they only define it for non-skew tableau. But the definition extends trivially to skew-shapes as well.
Can you give a reference to a (mathematical) definition?
Added the definition of major index.