Subring is not necessarily ideal, where to start?
114329
Example of subring that is not an ideal
63192
A chain ring with Krull dimension greater than one
45627
Find a sub-ring of M(2, $\mathbb{Q}$) which is isomorphic to $\mathbb{Q}$
148569
Embeddings $A → B → A$, but $A \not\cong B$?
59419
Crafty solutions to the following limit
4507
Localization of a ring which is not a domain
100743
small string optimization for vector?
148804
Norm-Euclidean rings?
141100
Nontrivial subring with unity different from the whole ring?
101303
How do I specify a dynamic position for the start of substring?
154167
How do you set attributes on SubValues?
121465
$R[x]$ has a subring isomorphic to $R$.
127431
What is the equation for a string fixed at both ends without simplifying assumptions?
133738
Can a ring without a unit element have a subring with a unit element?
136389
Finding an isomorphic subring of matrices
110726
Example of a non-gcd domain
115031
How to join two strings one of which is Subscript?