If XXX is a discrete random variable such that P(X=k)=C⋅2kk!P(X=k) = C \cdot \frac{2^k}{k!}P(X=k)=C⋅k!2k for k=0,1,2,…k=0, 1, 2, \dotsk=0,1,2,…, what is CCC?
e−2e^{-2}e−2
e−1e^{-1}e−1
e2e^{2}e2
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