Algebraic properties and dismantlability of finite posets
✍ Scribed by Benoit Larose; László Zádori
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 554 KB
- Volume
- 163
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
We show that every finite connected poser which admits certain operations such as Gumm or J6nsson operations, or a near unanimity function is dismantlable. This result is used to prove that a finite poset admits Gumm operations if and only if it admits a near unanimity function. Finite connected posets satisfying these equivalent conditions are characterized by the property that their idempotent subalgebras are dismantlable. As a consequence of these results we obtain that the pro01em of determining if a finite poset admits a near unanimity function is decidable.
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