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Find a sequence

Algebra Level 3

A sequence \(\{x_n\}\) is defined as follows: \[x_1 =1 \ , \ x_{n+1} = x_n^2 +2x_n \ (n=1,2,3,\cdots).\] Find \(x_7\).

\[2^{32}\] \[2^{64} \] \[2^{32} -1\] \[2^{64} -1\]

Excel in math and science

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by Sandeep Mehra

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