On Postnikov's hook length formula for binary trees
نویسندگان
چکیده
We present a combinatorial proof of Postnikov’s hook length formula for binary trees. AMS Classification: 05A15, 05A19
منابع مشابه
Yet Another Generalization of Postnikov's Hook Length Formula for Binary Trees
— We discover another one-parameter generalization of Postnikov's hook length formula for binary trees. The particularity of our formula is that the hook length h v appears as an exponent. As an application, we derive another simple hook length formula for binary trees when the underlying parameter takes the value 1/2.
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— We find two new hook length formulas for binary trees. The particularity of our formulas is that the hook length h v appears as an exponent. Consider the set B (n) of all binary trees with n vertices. It is well-known that the cardinality of B (n) is equal to the Catalan number (see, e.g., [9, p.220]): (1) T ∈B(n) 1 = 1 n + 1 2n n. For each vertex v of a binary tree T ∈ B (n) the hook length ...
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 29 شماره
صفحات -
تاریخ انتشار 2008