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arXiv · 1502.06012

On the Matrix-Element Expansion of a Circulant Determinant

Jerome Malenfant
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Abstract

The determinant of an $N \times N$ circulant matrix $M = {\rm CIRC}[x_0, x_1, ..., x_{N-1}$] can be expanded in the form det$ ~M= \sum C_{a_0 a_1 ...a_{N-1}} x_{a_0} x_{a_1}...x_{a_{N-1}}$. By using the generating function of a restricted, mod-$N$ partition function, we derive a formula for the coefficients in this expansion as finite sums over products of binomial coefficients with integer variables.

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Jerome Malenfant. 2015-02-20. On the Matrix-Element Expansion of a Circulant Determinant. https://arxiv.org/abs/1502.06012

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