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- Is a subring a UFD? [duplicate] 2 answers
How to show that when $K$ is a field, $K[X^2,X^3]$ is not factorial? What in fact is the ring $K[X^2,X^3]$, is this all the polynomials with exponents $2,3,6,8,9,...$?
We need to show that there is some $f\in K[X^2,X^3]$ such that:
Where $u$ is a unit.