The "Foxtrot series" is a mathematical sum that appeared in the June 2, 1996 comic strip FoxTrot by Bill Amend (Amend 1998, p. 19; Mitchell 2006/2007). It arose from a convergence testing problem in a calculus book by Anton, but was inadvertently converted into a summation problem on an alleged final exam by the strip's author:
(1)
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The sum can be done using partial fraction decomposition to obtain
(2)
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(3)
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(4)
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(5)
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(OEIS A127198), where and the last sums have been done in terms of the digamma function and symbolically simplified.