e and factorial identity dream

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$$ne^n = \sum_{k=0}^{\infty}\frac{n^k(n - k)^2}{k!}.$$

 

I dreamt of this identity yesterday night
but I don't even know how to prove it

lol

Comments

  1. Anonymous1/21/2022

    how in the world do you dream of a identity
    i only get dreams about candyland

    ReplyDelete

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