Use Mathematical Induction to prove that $^{2n}C_n < 2^{2n-2}$.

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Use Mathematical Induction to prove that $$^{2n}C_n < 2^{2n-2}$$ when $n\geq5$.

My attempt :

For $n=1$ , I got $LHS = 252 < RHS = 256$

Assumption : $$^{2k}C_k < 2^{2k-2}$$

For $n=k+1$,

$$^{2(k+1)-2}C_{k+1} = 2\times ^{2k+1}C_{k}$$

$$= 2\times \{^{2k}C_{k}+^{2k}C_{k-1}\}$$

$$ < 2\times \{2^{2k-2}+^{2k}C_{k-1}\}$$

how can I proceed from this step?