Abstract
Extending a result of Kleitman et al. [7] it is shown that the vertices on the convex hull off-vectors of all antichains of a poset come from antichains which are the unions of full orbits of the automorphism group.
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Frankl, P. The convex hull of antichains in posets. Combinatorica 12, 493–496 (1992). https://doi.org/10.1007/BF01305241
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DOI: https://doi.org/10.1007/BF01305241