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arXiv · 1106.4997

On the number of hypercubic bipartitions of an integer

Geir Agnarsson
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Abstract

We revisit a well-known divide-and-conquer maximin recurrence $f(n) = \max(\min(n_1,n_2) + f(n_1) + f(n_2))$ where the maximum is taken over all proper bipartitions $n = n_1+n_2$, and we present a new characterization of the pairs $(n_1,n_2)$ summing to $n$ that yield the maximum $f(n) = \min(n_1,n_2) + f(n_1) + f(n_2)$. This new characterization allows us, for a given $n\in\nats$, to determine the number $h(n)$ of these bipartitions that yield the said maximum $f(n)$. We present recursive formulae for $h(n)$, a generating function $h(x)$, and an explicit formula for $h(n)$ in terms of a special representation of $n$.

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Geir Agnarsson. 2011-06-24. On the number of hypercubic bipartitions of an integer. https://arxiv.org/abs/1106.4997

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