What is an example of a finite ring $R$ with unity and a subring $S$ of $R$ that is not a ring with unity?
2026-02-23 02:56:02.1771815362
Example of a finite ring with identity containing a ring without identity
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$\mathbb{Z}/8\mathbb{Z}$ is a unital finite ring, and the subring consisting of the elements $\{0,2,4,6\}$ is finite, but with no unit.