Kybernetika 56 no. 5, 886-902, 2020

One-adhesive polymatroids

Laszlo CsirmazDOI: 10.14736/kyb-2020-5-0886


Adhesive polymatroids were defined by F. Matúš motivated by entropy functions. Two polymatroids are adhesive if they can be glued together along their joint part in a modular way; and are one-adhesive, if one of them has a single point outside their intersection. It is shown that two polymatroids are one-adhesive if and only if two closely related polymatroids have joint extension. Using this result, adhesive polymatroid pairs on a five-element set are characterized.


polymatroid, entropy function, amalgam, adhesive polymatroid, polyhedral cone


05B35, 94A15, 52B12


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