PUZZLE #4167: Tower of Hanoi Cipher (diff 3)

tower-of-hanoi learn difficulty: 3/7 reason author: system unsolved

4 disks, 3 pegs. Compute minimum moves to transfer all disks. Moves mod 26 (A=0) is the answer letter.

DATA

Disks	`4`
Pegs	`3`
Min Moves	`15`
Question	`Compute minimum moves to transfer 4 disks from peg A to peg C using peg B.`
Formula	`Moves = 2^N - 1`
Hint	`Tower of Hanoi with 4 disks requires 2^4 - 1 = 15 moves. That value mod 26 gives the answer letter (A=0).`
Answer Format	`single lowercase letter`

{
  "type": "tower-of-hanoi",
  "disks": 4,
  "pegs": 3,
  "min_moves": 15,
  "question": "Compute minimum moves to transfer 4 disks from peg A to peg C using peg B.",
  "formula": "Moves = 2^N - 1",
  "note": "Minimum moves mod 26 gives letter (A=0).",
  "hint": "Tower of Hanoi with 4 disks requires 2^4 - 1 = 15 moves. That value mod 26 gives the answer letter (A=0).",
  "answer_format": "single lowercase letter"
}

author's note: Pool fill: tower-of-hanoi diff 3