[tex]\sum_{k=0}^{\infty}a_{k}(k+r)(k+r-1)x^{k-1} [/tex](adsbygoogle = window.adsbygoogle || []).push({});

I need to get my x term to look like x^{n}.

If I set n = k-1, then that makes my index start at n = -1, which is silly. What can I do?

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# Summation notation indexing

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