jinksys
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I understand that if given the following series:
[tex]\sum _{n=1}^{\infty } \frac{1}{n(n+3)}[/tex]
I can break it up using partial fraction decomposition into:
[tex]\sum _{n=1}^{\infty } \frac{1}{3n}-\frac{1}{3n+9}[/tex]
If I start listing the values of [tex]n_1,n_2[/tex], etc, I can see the cancellation pattern and find the sum.
This process seems tedious, is there another way of doing these problems?
Wikipedia says:
* Let k be a positive integer. Then
[tex]\sum^\infty_{n=1} {\frac{1}{n(n+k)}} = \frac{H_k}{k}[/tex]
where Hk is the kth harmonic number. All of the terms after 1/(k − 1) cancel.
But I'm not sure what the 1/(k - 1) means, nor do I understand the harmonic number bit either.
[tex]\sum _{n=1}^{\infty } \frac{1}{n(n+3)}[/tex]
I can break it up using partial fraction decomposition into:
[tex]\sum _{n=1}^{\infty } \frac{1}{3n}-\frac{1}{3n+9}[/tex]
If I start listing the values of [tex]n_1,n_2[/tex], etc, I can see the cancellation pattern and find the sum.
This process seems tedious, is there another way of doing these problems?
Wikipedia says:
* Let k be a positive integer. Then
[tex]\sum^\infty_{n=1} {\frac{1}{n(n+k)}} = \frac{H_k}{k}[/tex]
where Hk is the kth harmonic number. All of the terms after 1/(k − 1) cancel.
But I'm not sure what the 1/(k - 1) means, nor do I understand the harmonic number bit either.