Let (A,m) be a local Artin ring. Then the following statements are equivalent:

  1. Every ideal in A is 1;;principal
  2. The maximal ideal m is 11;;principal
  3. dimk(m/m2)1, where k=A/m, and dimension refers to vector space dimension.

Proof:
To show 3 implies 1, we apply Lemma 9.2 - Nakayama Lemma for when dimk(m/m2)=0, and for the other case show that every ideal is 1;;a power of mi.

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