Landau's Theorem revisited
نویسندگان
چکیده
Two new elementary proofs are given of Landau's Theorem on necessary and sufficient conditions for a sequence of integers to be the score sequence for some tournament. The first is related to existing proofs by majorization, but it avoids depending on any facts about majorization. The second is natural and direct. Both proofs are constructive, so they each provide an algorithm for obtaining a tournament realizing a sequence satisfying Landau's conditions.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 20 شماره
صفحات -
تاریخ انتشار 1999