Summability of alterations of convergent series

[摘要] The effect of splitting, rearrangement, and grouping series alterations on the summability of a convergent series byℓ−ℓandcs−csmatrix methods is studied. Conditions are determined that guarantee the existence of alterations that are transformed into divergent series and into series with preassigned sums.

[学科分类] 数学（综合）