What happens if I change the norm of an absolute convergent series?

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Let us consider the topological vector space $\mathbb{C}$ equipped with the euclidean topology.

We know that a series of complex numbers $\sum_{n=1}^{\infty}a_n$ is said to be absolutely convergent iff $\sum_{n=1}^{\infty}||a_n||$ is convergent.

I've always assumed that by $||\cdot||$ we mean, when considering absolute convergence, the euclidean norm. Now that I'm reviewing my notes, I'm wondering why we usually make this assumption. What happens if I consider different kinds of norm?

In particular I'd like to know

  • Does absolute convergence depend on the choice of $||\cdot||$ ?
  • If I change the norm, does absolute convergence still imply convergence?
  • Is there any book or paper addressing this question?