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Property: free
Definition: $M$ is isomorphic to a direct sum of copies of $R_R$.
Reference(s):
(No citations retrieved.)
Metaproperties:
This property
does not
have the following metaproperties
passes to quotients (Counterexample:
$M_{ 3 }$
is a homomorphic image of
$M_{ 16 }$
)
Modules
Name
$(x + (x,y)^2)$
$(x)/(x^2)$
$\bigoplus_{i=0}^\infty \mathbb Q$
$\bigoplus_{i=1}^\infty F_2$
$\mathbb Q$
$\mathbb Q\times \frac{\mathbb Z}{p\mathbb Z}$, where $p$ is prime
$\mathbb Q^n$
$\mathbb Z\times \frac{\mathbb Z}{p\mathbb Z}$, $p$ prime
$Z(p^\infty)$: the Prüfer $p$ group
A 2-generated faithful torsion module
Uniserial, not endolocal module
$2$-adic integers: $\mathbb Z_2$
$\bigoplus_{i=1}^\infty \mathbb Z$
$\bigoplus_{i=1}^\infty \mathbb Z_{(2)}$
$\mathbb R[x_1,x_2,x_3,\ldots]$
$\mathbb Z$
$M_n(\mathbb Q)$
$T_2(F_2)$
Finitely cogenerated, not Artinian
Indecomposable, not uniform module
Interval monoid ring (right regular module)