# [Jelly], 9 bytes

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[Try it online!][TIO-k352nqes]

[Jelly]: https://github.com/DennisMitchell/jelly
[TIO-k352nqes]: https://tio.run/##y0rNyan8///opIJDyx81zDy8Pf7kdKOA/4fbHzWtifz/P9pQBwhjdcC0EZg20jEG0kASLA6iTYA0kATLGwP5prEA "Jelly – Try It Online"

Based on the closed form expression given in the question.