Littlewood-Richardson coefficients and Kazhdan-Lusztig polynomials
  We show that the Littlewood-Richardson coefficients are values at 1 of certain parabolic Kazhdan-Lusztig polynomials for affine symmetric groups. These q-analogues of Littlewood-Richardson multiplicities coincide with those previously introduced in terms of ribbon tableaux. 
Bernard Leclerc, Jean-Yves Thibon