Question

1.求0+1+3+7+15+……+2^n-1的值.N的值由键盘输入.用asp.net语言来编写程序!

Answer 1

1、原式=2^0-1+2^1-1--------2-+2^n-1

=2^0+2^1+2^2+--------+2^n-(n+1)

=2^(n+1)-2^0-(n+1)

=2^(n+1)-n-2

别的就不明白了