We succeeded in simulating the many-particle A+B <----> C reaction in three-dimensions to sufficiently long-times, revealing the ultimate asymptotic approach to equilibrium. The deviation from equilibrium is a t(-3/2) power-law, with a concentration-dependent prefactor which agrees quantitatively with the theoretical prediction. The logarithmic derivative of the deviation from equilibrium undergoes through a maximum and minimum before converging to 3/2. We conjecture that this behavior could signal the onset and termination of the local concentration relaxation.