1+3+7+9+…+(2n-1)+(2n+1)+(2n+3)等于几

1+3+7+9+…+(2n-1)+(2n+1)+(2n+3)等于几 1+3+5+7+9+……+(2n-1)+(2n+1)+(2n+3)等于几? 证明不等式：(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n 1,2,4,7,11,16.n n等于几 n(n+1)(n+2)等于多少? (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 lim(1/n^2+4/n^2+7/n^2+…+3n-1/n^2) [3n(n+1)+n(n+1)(2n+1)]/6+n(n+2)化简 +(n-1)!+(n-2)!+.+(n-n)!等于什么? 化简(n+1)(n+2)(n+3) 1乘2+2乘3+3乘4+.n(n+1)等于几分之几n(n+1)(n+2) ∵ n（n+1）（n+2）（n+3）+1 等于?