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new ring: Right-not-left free ideal ring
JeremyRickard suggested an example of a right free ideal ring that does not satisfy the ACC on left principal ideals.
new ring: the Toeplitz-Jacobson algebra
Thanks dbossaller for the excellent example of a ring which has IBN but is not Dedekind finite.
New ring: Cozzens' simple left PID
This example due to Cozzens is often cited as showing how much asymmetry is possible in simple rings.
new theorem: Did you know...
Commutative von Neumann regular rings are characterized by the fact that their polynomial ring over a single variable is semihereditary? That is the content of this theorem of Camillo.
new ring: Almost-but-not-quite-Dedekind
Added an example of an almost Dedekind ring which isn't Dedekind. In particular it has Krull dimension 1, all of its localizations are Noetherian, but it itself is not Noetherian.
New ring: asymmetry of PF
This is a ring which is one-sided pseudo-Frobenius. The construction is involved, and not complete yet. Also, if you had any trouble visiting the theorems section recently, please try again. I fixed a bug there.
new ring: Asymmetry of principally injective
This is an example of a ring which is one-sided principally injective.
New rings: V domains
Added this ring and this ring, examples of simple right V domains, which I hear are pretty rare.
Site news: Ring maps
I posted a few graphs of implications between ring properties. This is the first time I've regenerated the graphs in a long time, so there are probably problems. Please let me know if you find any. Thanks!
site news: 100th ring winner (and more!)
Congratulations MatheinBoulomenos for the winning submission! The next several rings are submissions from the contest too, so check them out. Also thanks to kc_kennylau for working so hard filling in a lot of gaps, especially around ring cardinalities.

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