0 + 1^2 = 1 1 + 2^2 = 5 5 + 3^2 = 14 14 + 4^2 = 30 30 + 5^2 = 55 55 + 6^2 = 91 91 + 7^2 = 140 An = 1^2 + 2^2 + 3^2 + ...+ n^2
1.5.14.30.55.91找规律添数答案是140 怎么来的?
0 + 1^2 = 1 1 + 2^2 = 5 5 + 3^2 = 14 14 + 4^2 = 30 30 + 5^2 = 55 55 + 6^2 = 91 91 + 7^2 = 140 An = 1^2 + 2^2 + 3^2 + ...+ n^2