  We give explicit analytical expressions for the partition function of
$U(N)_{k}\times U(N+M)_{-k}$ ABJ theory at weak coupling ($k\rightarrow \infty
)$ for finite and arbitrary values of $N$ and $M$ (including the ABJM case and
its mass-deformed generalization). We obtain the expressions by identifying the
one-matrix model formulation with a Meixner-Pollaczek ensemble and using the
corresponding orthogonal polynomials, which are also eigenfunctions of a
$su(1,1)$ quantum oscillator. Wilson loops in mass-deformed ABJM are also
studied in the same limit and interpreted in terms of $su(1,1)$ coherent
states.
