BPS invariants for resolutions of polyhedral singularities

We study the BPS invariants of the preferred Calabi-Yau resolution of ADE polyhedral singularities C^3/G given by Nakamura's G-Hilbert schemes. Genus 0 BPS invariants are defined by means of the moduli space of torsion sheaves as proposed by Sheldon Katz. We show that these invariants are equal to half the number of certain positive roots of an ADE root system associated to G. This is in agreement with the prediction via Gromov-Witten theory.