Abel's test is an important tool for handling semi-convergent series. If a series has the form
where the partial sums BN = b0 + ··· + bn are bounded, λn has bounded variation, and lim λn Bn exists:
then the series ∑ an is convergent. This applies to the pointwise convergence of many trigonometric series, as in
with 0 < x < 2π. Abel's method consists in writing bn+1 = Bn+1 − Bn, and in performing a transformation similar to integration by parts (called summation by parts), that relates the given series ∑ an to the absolutely convergent series

若能收集到该词条相关资料的跟帖者给予奖励，根据收集资料的水平给予10～200不等的论坛币，当然也可以谈谈自己的观点、其应用领域、上传资料、相关软件介绍等等，请大家尽量不要复制一些搜索引擎很容易收集到的资料。

     我每天都会发送不等数量的词条，所以诚邀不同统计背景的各路大侠发表评论。

     欢迎大家多多跟帖！要数量也要质量哟