Let XXX be a random variable such that P(X=k)=12k+1P(X=k) = \frac{1}{2^{k+1}}P(X=k)=2k+11 for k=0,1,2,…k=0, 1, 2, \dotsk=0,1,2,…. Calculate E[X2]E[X^2]E[X2].
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