3483 A Very Simple Problem 数论+矩阵的应用

看着别人的解题报告写的，推导过程还是不太懂 求sum(x^kk^x) k=1~N x^(k+1)(k+1)^x=x^kx(k+1)^x 然后用二项式定理展开(k+1)^x即可 例如当x=4时 | 1x 0 0 0 0 0 | |x^kk^0| |x^(k+1)(k+1)^0| | 1x 1x 0 0 0 0 | |x^kk^1| |x^(k+1)(k+1)^1| | 1x 2x 1x 0 0 0 ||x^kk^2|=|x^(k+1)(k+1)^2| | 1x 3x 3x 1x 0 0 | |x^kk^3| |x^(k+1)(k+1)^3| | 1x 4x 6x 4x 1x 0 | |x^kk^4| |x^(k+1)*(k+1)^4| | 1x 4x 6x 4x 1x 1x | | S(k) | | S(k+1) |