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Clones, order varieties, near unanimity functions and holes

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A finite ordered set has an order preserving majority function if and only if it is a retract of a direct product of fences.

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The authors' research was supported by grants from the NSERC of Canada.

Communicated by M. Pouzet

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Quackenbush, R.W., Rival, I. & Rosenberg, I.G. Clones, order varieties, near unanimity functions and holes. Order 7, 239–247 (1990). https://doi.org/10.1007/BF00418652

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AMS subject classification (1980)

  • 06A10

Key words

  • Clone
  • hole
  • order variety