Question

设数列{an}，{an^2}(n属于N*)都是等差数列，若a1=2则a2^2+a3^3+a4^4+

设数列{an}，{an^2}(n属于N*)都是等差数列，若a1=2则a2^2+a3^3+a4^4+a5^5等于?

Answer 1

数列{an},{an^2}都是等差数列
a1+a3=2a2 , a1^2+a3^2=2a2^2
把a1=2代入得2+a3=2a2 , 4+a3^2=2a2^2
解得a2=a3=2
所以a1=a2=a3=a4=a5=2代入即得答案60