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arXiv 0910.0903math.CO
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关于n立方图的平衡着色

On Balanced Colorings of the n-Cube

William Y. C. Chen, Larry X. W. Wang

摘要:

n维欧几里得空间中的n立方图的2-着色可以被认为是给顶点分配1或0的权重。这样一个着色的n立方图如果其质心与几何中心重合,则称其为平衡的。令$B_{n,2k}$为具有2k个顶点且权重为1的n立方图的平衡2-着色数。Palmer、Read和Robinson指出,对于$n\geq 1$,序列$\{B_{n,2k}\}_{k=0, 1 ... 2^{n-1}}$是对称的和单峰的。我们给出了这个猜想的一个证明。对于固定的k,我们还提出了一个关于$B_{n,2k}$的对数正态性的猜想,并通过概率的方法证明了当n足够大时该猜想成立.

英文摘要:

A 2-coloring of the n-cube in the n-dimensional Euclidean space can be considered as an assignment of weights of 1 or 0 to the vertices. Such a colored n-cube is said to be balanced if its center of mass coincides with its geometric center. Let $B_{n,2k}$ be the number of balanced 2-colorings of the n-cube with 2k vertices having weight 1. Palmer, Read and Robinson conjectured that for $n\geq 1$, the sequence $\{B_{n,2k}\}_{k=0, 1 ... 2^{n-1}}$ is symmetric and unimodal. We give a proof of this conjecture. We also propose a conjecture on the log-concavity of $B_{n,2k}$ for fixed k, and by probabilistic method we show that it holds when n is sufficiently large.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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