By using the density theory of theories of Numbers, the article gives the density discrimination method determining the convergence and divergence characteristic of the positive term series.

借鉴数论方法中的密率论，给出判别正项级数敛散性的密率判别法，此方法特别适用于判定一些较难或不能给出通项表达式的级数的敛散性。

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This week in our series, Larry West and Frank Oliver talk about the first term of President Ulysses Grant.

VOA: special.2010.02.18

This week in our series, Harry Monroe and Kay Gallant tell about Grants second term in office.

VOA: special.2010.02.25

Unlike feature films, where projects are brief and windows of availability can be made, TV talent often gets locked up on other pilots or long-term series and has difficulty making time.

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What is the term for the series of spending cuts and tax increases that would have gone into effect if Congress hadn't reached an agreement this week?

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What we need right now, in the immediate term, is a series of massive public works projects.

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