In this paper, the general high order equal ratios sequence have been studied by generating functions and recursion relations.

本文利用母函数和递推关系求解一般高阶等比序列，得到了这类序列的一般解。

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All things being equal, over time those funds that have the lowest expense ratios will outperform all other funds.

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In fact there only circumstance where such an index has value is when the Sharpe ratios of all component stocks and the correlations between all pairs of stocks in the index are equal.

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