1+2+2的平方+2的立方+2的（立方+1）·····+2的（立方+9）要过程1+2+2的平方+2的立方+2的（立方+1）················2的（立方+6）前面错了
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1+2+2的平方+2的立方+2的（立方+1）·····+2的（立方+9）要过程1+2+2的平方+2的立方+2的（立方+1）················2的（立方+6）前面错了
1+2+2的平方+2的立方+2的（立方+1）·····+2的（立方+9）
要过程
1+2+2的平方+2的立方+2的（立方+1）················2的（立方+6）前面错了
1+2+2的平方+2的立方+2的（立方+1）·····+2的（立方+9）要过程1+2+2的平方+2的立方+2的（立方+1）················2的（立方+6）前面错了
这是个等比数列求和问题.S=(1-2^10)/(1-2)=2^10-1=1023
直接用等比公式计算就可以了
n = 1, S = 2^0 = 1
n = 2, S = 2^0 + 2^1 = 1 + 2 = 3
n = 3, S = 2^0 + 2^1 + 2^2 = 1 + 2 + 4 = 7
n = 4, S = 2^0 + 2^1 + 2^2 + 2^3 = 1 + 2 + 4 + 8 = 15
n = n, S = 2^0 + 2^1 + 2^2 + 2^3 + ...
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n = 1, S = 2^0 = 1
n = 2, S = 2^0 + 2^1 = 1 + 2 = 3
n = 3, S = 2^0 + 2^1 + 2^2 = 1 + 2 + 4 = 7
n = 4, S = 2^0 + 2^1 + 2^2 + 2^3 = 1 + 2 + 4 + 8 = 15
n = n, S = 2^0 + 2^1 + 2^2 + 2^3 + ....+ 2^(n-2) + 2^(n-1)
2S = 2 * (2^0 + 2^1 + 2^2 + 2^3 + .... + 2^(n-1)) = 2^1 + 2^2 + 2^3 + ....+ 2^(n-1) + 2^n
=>
S = 2S - S = 2^1 + 2^2 + 2^3 + .... + 2^n - (2^0 + 2^1 + 2^2 + 2^3 + .... + 2^(n-1)) = 2^n - 1
S = 2^0 + 2^1 + 2^2 + 2^3 + .... + 2^(n-1) = 2^n - 1
1+ 2^2 + 2^3 + ..... + 2^9 => n-1 = 9
n = 10 =>S = 2^10 - 1 = 1023
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