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Owlet puzzle #14

Released Sunday, July 19, 2026 UTC

65537
the answer for puzzle #14

The five clues

  1. A five-digit number.
  2. A Fermat prime.
  3. The fifth (and largest known) Fermat prime.
  4. Equal to 2¹⁶ + 1.
  5. Gauss proved the regular 65537-gon is constructible with compass and straightedge.

Backstory

F₄ = 65537 is prime; F₅ through F₃₂ are all composite. Only five known Fermat primes: 3, 5, 17, 257, 65537.

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