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Qfwfq
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Example of a ring with non-finitely generated unit group?

We all know Dirichlet's unit theorem —The well known Dirichlet's unit theorem states that the unit group of a maximal order in a quadratic number field is finitely generated of rank blah blah blah. I think it's pretty naive to expect a most radical generalization to hold, namely:

IntergalacticGeneralized Dirichlet unit theorem. UnitThe unit group of an associative unital ring with finitely generated additive group is finitely generated.

Is there any concrete counterexample?

Example of a ring with non-finitely generated unit group

We all know Dirichlet's unit theorem — unit group of maximal order in quadratic number field is finitely generated of rank blah blah blah. I think it's pretty naive to expect most radical generalization to hold, namely:

Intergalactic Dirichlet unit theorem. Unit group of an associative unital ring with finitely generated additive group is finitely generated.

Is there any concrete counterexample?

Example of a ring with non-finitely generated unit group?

The well known Dirichlet's unit theorem states that the unit group of a maximal order in a quadratic number field is finitely generated of rank blah blah blah. I think it's pretty naive to expect a most radical generalization to hold, namely:

Generalized Dirichlet unit theorem. The unit group of an associative unital ring with finitely generated additive group is finitely generated.

Is there any concrete counterexample?

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Denis T
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Example of a ring with non-finitely generated unit group

We all know Dirichlet's unit theorem — unit group of maximal order in quadratic number field is finitely generated of rank blah blah blah. I think it's pretty naive to expect most radical generalization to hold, namely:

Intergalactic Dirichlet unit theorem. Unit group of an associative unital ring with finitely generated additive group is finitely generated.

Is there any concrete counterexample?