Check if following functional is continuous

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Check if following funtional is continuous

$ R[X]\ni p \to p(0)p \in R[X] $

towards norm:

$||p|| = \sum_{n=1} 2^{-n}|p(\frac{1}{n})|$

I've started:

$||p|| = sup_{\sum_{n=1} 2^{-n}|p(\frac{1}{n})|\le1}\{\sum_{n=1} 2^{-n}|p(0)p(\frac{1}{n})|\} \le p(0)$

But I'm not able to give a counterexample, which shows that this functional is discontinuous indeed.