求和:C1n+2C2n+3C3n+…+nCnn=______.(n∈N*) 发布时间:2017-05-16 16:17 │ 来源:www.tikuol.com 题型:填空题 问题: 求和:C1n+2C2n+3C3n+…+nCnn=______.(n∈N*)