2^(2011)+2^(2010)=2^(2010)[2+1] = 3*2^(2010),素因子只有3和2.不能被5整除.
题目应是2^(2012)+2^(2010)=2^(2010)[4+1]=5*2^(2010),素因子只有5和2,能被5整除.
3^(n+3)-4^(n+1) + 3^(n+1) - 2^(2n)
=3^(n+1)[9+1] - 2^(2n)[4 + 1]
=10*3^(n+1) - 2^(2n-1)*10
=10[3^(n+1)-2^(2n-1)]能被10整除