I asked a question about this series;
(1−12)+(13−14)(1−12+13)+(15−16)(1−12+13−14+15)+(17−18)(1−12+13−14+15−16+17)+...
in a previous thread and something else about it that I'd like to know is if there is a name for series where the coefficient of each term is a partial sum? Furthermore, is there a general method for finding the closed form sums of such series?
Answer
There is no special name since what you have is just a double summation instead of a single summation. Your series is nothing but
∞∑n=02n+1∑k=1(12n+1−12n+2)((−1)k−1k)
which can also be written as a single summation
∞∑n=0(12n+1−12n+2)(H2n+1−Hn)
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