从①出发进行推导有 2>(Q-r(+k2QP) r=Q+1 ≤h∑Q+1P+k(Q-)P) r=0 r=Q+2 收+∑P)-k20→∑P2 k+h从①出发进行推导有      = + + =  = = +  + − + − + r Q 2 Q 1 r 0 r Q 1 Q r 0 h (Q 1 r)P(r) k (r -Q -1)P(r) h (Q r)P(r) k (r -Q)P(r) (k h) P(r) k 0 Q r 0 +  −  = k h k P(r) Q r 0 +   =