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Ira Gessel
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More generally, $$\sum_{k=0}^\infty F_{n+k} \frac{x^k}{k!} = e^x\sum_{k=0}^\infty F_{n-k}\frac{x^k}{k!},$$ which is equivalent to Will Sawin's identity.

Ira Gessel
  • 17k
  • 1
  • 58
  • 80