… We show that normalized Schur polynomials are strongly logconcave. As a consequence,
we obtain Okounkov’s log-concavity conjecture for Littlewood–Richardson coefficients in the
special case of Kostka numbers. … We prove several log-concavity properties of Schur
polynomials. An operator that turns generating functions into exponential generating functions
will play an important role. This linear operator, denoted N, is defined by the condition …