2[10^(n+1)]^2*100*5^(2n)*2^(2n-1)

2^n/n*(n+1) 证明不等式：(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n Sn=n(n+2)(n+4)的分项等于1/6[n(n+2)(n+4)(n+5)-(n-1)n(n+2)(n+4)]吗? 证明(1+2/n)^n>5-2/n（n属于N+,n>=3) [3n(n+1)+n(n+1)(2n+1)]/6+n(n+2)化简 化简(n+1)(n+2)(n+3) n(n+1)(n+2)数列求和 n(n+1)(n+2)等于多少? 阶乘(2n-1)!=（2n)!/(2^n*n! 化简[n^2+(n+1)^2]/n(n+1) 化简额 计算：n(n+1)(n+2)(n+3)+1 lim[(n+3)/(n+1))]^(n-2) 【n无穷大】