13……(2n-1)(2n)(2n-2)……2逆序数怎么求

2^n/n*(n+1) 证明不等式：(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n 证明(1/n)^n+(2/n)^n+……+(n-1/n)^n > (n-1)/2(n+1) 对任意n正整数成立 (1/(n^2 n 1 ) 2/(n^2 n 2) 3/(n^2 n 3) ……n/(n^2 n n)) 当N越于无穷大的极限(1/(n^2+n+1 ) +2/(n^2+n+2) +3/(n^2+n+3) ……n/(n^2+n+n)) 当N越于无穷大的极限 1+(n+2)+(2n+3)+(3n+4)+(4n+5)+……((n-1)n+n)的答案 {[(1+n)(2+n)(3+n)……(n+n)]^(1/n)}/n当趋向正无穷 求其极限 证明不等式：(1/n)的n次方+(2/n)的n次方+……+(n/n)的n次方 e^(1/n)+e^(2/n)+e^(3/n)+…+e^(n-1/n)+e^(n/n)=? (n+2)!/(n+1)! 数学不等式证明题n=1,2,……证明：(1/n)^n+(1/2)^n+……+(n/n)^n第二个是(2/n)^n 设f(n)=1/n+1+1/n+2+1/n+3+……+1/3n(n∈N+),则f(n+1)-f(n)=? C(n,0)+C(n,1)+C(n,2)+…+C(n,n-2)+C(n,n-1)+C(n,n)为什么等于什么 证明:(3^n)*(2^1/n)>(3^n)+(2^1/n)……n属于正整数 lim(1/n^2+4/n^2+7/n^2+…+3n-1/n^2) 证明1/(n+1)+1/(n+2)+1/(n+3)+……+1/(n+n) 组合：C（n,0）+C(n,1)+……+C(n,n)=n^2 VB编程n!+(n+1)!+(n+2)!+(n+3)!+……+(n+m)!要有控件 [n+(n+1)+(n+2)+……+1]化简