I'm sorry if this isn't an appropriate question for MO. I've been reading here for a while, but I still haven't got a good grasp of what's a <i>good</i> question.<br /><br>Given a field A and the polynomial ring A[x], we order the elements of A in any sequence and we define the isomorphism $f\colon A\to A[x]$ such that every element a<sub>n</sub>$\mapsto$a<sub>n</sub> x<sup>n</sup>, a<sub>n</sub> $\in$ A, x<sup>n</sup> $\in$ A[x].

Can this be considered an alternate definition for A[x], is it just wrong, or is it the same as the canonical one?

Andy