) 中图学技术大荸学系 University of Science and Technology of China DEPARTMENT OF MATHEMATICS (n+1)m2次运算 b-∑ 2n i+1 nn数 学 系 University of Science and Technology of China DEPARTMENT OF MATHEMATICS , , ,1 2 2 2 1 1 1 1 2 1      i n u b u x x u u u u u u A i i n j i i i j j i n n n n = −  =               = = + ③ （n＋1）n/2次运算