Abstract Algebra – Example of a Finite Non-Commutative Ring Without Unity

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Give an example of a finite, non-commutative ring, which does not have a unity.

I can't think of any thing which fits this question. I was thinking $M_2(\mathbb{R})$ but it has the identity. Any help is appreciated.

Best Answer

There are many examples in this spirit: the $n\times n$ matrices over a finite field with bottom row zero.