2026/109/1-2 (5)
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DOI: 10.5486/PMD.2026.10407
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pp. 93-101
Some examples related to squares of elements in rings
Authors:
Grigore Călugăreanu 
Abstract:
We provide a $2\times 2$ integral matrix that is not fine yet its square is fine. Additionally, we characterize the rings in which the square of every element is idempotent.
Keywords: idempotent square, clean, nil-clean, fine
Mathematics Subject Classification: 16U40, 16U40, 16R50