Microcanonical distribution for black hole with allowance for nonadditivity

It is shown that with allowance for nonadditivity the (canonical) distribution for a black hole transforms to a (microcanonical) distribution which depends on nonadditive integrals of the motion and represents a nonlinear function of energy - the square of black hole mass. From a comparison with the standard microcanonical distribution it is found that the statistical weight of black hole should be proportional to the black hole area. A definition of the black hole entropy consistent with the statistical weight is proposed.