Minimizing the weight of the union-closure of families of two-sets

Uwe Leck, Ian Roberts, Jamie Simpson

    Research output: Contribution to journalArticleResearchpeer-review

    Abstract

    It is proved that, for any positive integer m, the weight of the unionclosure of any m distinct 2-sets is at least as large as the weight of the union-closure of the first m 2-sets in squashed (antilexicographic) order, where all i-sets have the same non-negative weight w i with w i ? w i+1 for all i, and the weight of a family of sets is the sum of the weights of its members. As special cases, solutions are obtained for the problems of minimising size and volume of the union-closure of a given number of distinct 2-sets.
    Original languageEnglish
    Pages (from-to)67-73
    Number of pages7
    JournalAustralasian Journal of Combinatorics
    Volume52
    Issue number1
    Publication statusPublished - 2012

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    Closure
    Union
    Distinct
    Non-negative
    Family
    Integer

    Cite this

    Leck, Uwe ; Roberts, Ian ; Simpson, Jamie. / Minimizing the weight of the union-closure of families of two-sets. In: Australasian Journal of Combinatorics. 2012 ; Vol. 52, No. 1. pp. 67-73.
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    Leck, U, Roberts, I & Simpson, J 2012, 'Minimizing the weight of the union-closure of families of two-sets', Australasian Journal of Combinatorics, vol. 52, no. 1, pp. 67-73.

    Minimizing the weight of the union-closure of families of two-sets. / Leck, Uwe; Roberts, Ian; Simpson, Jamie.

    In: Australasian Journal of Combinatorics, Vol. 52, No. 1, 2012, p. 67-73.

    Research output: Contribution to journalArticleResearchpeer-review

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