We give a new
q-(1+
q)-analogue of the
Gaussian coefficient, also known as the
q-binomial which, like the original
q-binomial
,
is symmetric in
k and
n-
k.
We show this
q-(1+
q)-binomial is more compact than
the one discovered by Fu, Reiner, Stanton, and Thiem.
Underlying our
q-(1+
q)-analogue
is a Boolean algebra decomposition
of an associated poset.
These ideas are extended to the Birkhoff transform of any finite poset.
We end with a discussion of higher analogues of the
q-binomial.
Received May 19 2016;
revised versions received August 31 2016; September 8 2016.
Published in Journal of Integer Sequences, September 11 2016.