毫____ 豪____ 漂____ 飘____
待____ 侍____ 挖____ 究____
滔____ 稻____ 旬____ 问____
已知等式 1n(n+1)=1n−1n+1 ,对任意正整数n都成立.计算: 11×2+12×3+13×4+⋯+1n(n+1) =____.
—I have got 1,000 already now.