Owlet puzzle #77
Released Sunday, September 20, 2026 UTC
512
the answer for puzzle #77
The five clues
- A three-digit power of two.
- A three-digit perfect cube in the low 500s.
- It equals 2⁹ = 8³ and is exactly half of 1024.
- One more than the minimum number of moves to solve Tower of Hanoi with 9 disks.
- The number of outcomes when flipping a coin nine times in sequence.
Backstory
512 = 2⁹ = 8³ = (2³)³ is the only three-digit perfect cube of a power of two: cubes of powers of two are 1, 8, 64, 512, 4096. It's also the size of a common SHA-2 hash block in bits and the number of centicubies… well, 8³.
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