Hilbert Sequence Space is not Locally Compact Hausdorff Space

Theorem
Let $A$ be the set of all real sequences $\left\langle{x_i}\right\rangle$ such that the series $\displaystyle \sum_{i \mathop \ge 0} x_i^2$ is convergent.

Let $\ell^2 = \left({A, d_2}\right)$ be the Hilbert sequence space on $\R$.

Then $\ell^2$ is not a locally compact Hausdorff space.

Proof
From Metric Space fulfils all Separation Axioms, $\ell^2$ is a Hausdorff space.

Let $x = \left\langle{x_i}\right\rangle \in A$ be a point of $\ell^2$.

From Point in Hilbert Sequence Space has no Compact Neighborhood, $x$ has no compact neighborhood.

Hence the result by definition of locally compact Hausdorff space.