collections/kTimesG's 80-bit key challenge

ktimesg/80_bit

Solved on 2024-11-02 after 1d 35m, key published. 0.005 BTC on a Bitcoin address, 1ECDLP8osCZHBB1LH5PVAUfFegeMgFb52q. Part of kTimesG's 80-bit key challenge.

IDktimesg/80_bit2024-11-01 → 2024-11-02
Puzzle / kTimesG's 80-bit key challenge

80_bit

bitcoinp2pkh solved

Record

bitcoinPuzzle({
  address: p2pkh("1ECDLP8osCZH…eMgFb52q", "90b881be7044…8ba92a12"),
  status: Status.Solved,
  key: hex("b40e7d34265a…6be5fe56"),
})
Prize
0.005 BTC
Key material
hex
Verification
verified
Solved
2024-11-02 · 1d 35m
tx 3
Trail
Explorerblockstream.info
Sourcebitcointalk.org/index.php?topic=1306983.msg64691846
Tryktimesg/80_bit in the playground
Address
1ECDLP8osCZHBB1LH5PVAUfFegeMgFb52q

hash160 90b881be7044a596b0ac843d84ff31278ba92a12

Balance
asking the explorer

Key

public key · compressed
03a61fc84b6429f07fc0edf25265ef7a0ced3cd9a0edea85e9f58b50b5d73f66e7
private key (hex)
b40e7d34265ab9533a64622bd1a188fb8abb8829af545169abad49b46be5fe56

Transactions

  1. funding2024-10-280.0025 BTCe4a2751bf7…43568b
  2. increase2024-10-280.0025 BTCa7d8b7f7a8…c5b2f9
  3. claim2024-11-020.00495 BTCdc8309f8b5…162f36

Hints

  1. 2024-10-16

    officialThe Hamming length of the range will therefore be 80 contiguous bits, but they may start anywhere.

    Sourcebitcointalk.org/index.php?topic=1306983.msg64639847

  2. 2024-11-01

    officialminKey = 0x659756abf6c17ca70e0000000000000000000140be6ddd93e441f8d4b4a85653b20b4cdcc5c748207a0daa16191d07a425d8080c276f9412472e0429e61bc355 maxKey = 0x659756abf6c17ca70fffffffffffffffffffff40be6ddd93e441f8d4b4a85653b20b4cdcc5c748207a0daa16191d07a425d8080c276f9412472e0429e61bc355

    Sourcebitcointalk.org/index.php?topic=1306983.msg64691846

    Published answer

    assert shift == 361; elem = shift_inv * (public_key - min_elem); assert idlp_key == 0x2d56cbf370cbeef9e80a; private_key = min_key | (idlp_key << shift); assert private_key % secp256k1.N == 0xb40e7d34265ab9533a64622bd1a188fb8abb8829af545169abad49b46be5fe56

    2024-11-02bitcointalk.org/index.php?topic=1306983.msg64695204

  3. 2024-11-01

    officialThe challenge involves correctly extracting pubkey from the raw TX, otherwise it's a no brainer.

    Sourcebitcointalk.org/index.php?topic=1306983.msg64691846

local record / balance from the explorer

@agntn/puzzles·MIT license· Public data about public puzzles. Balances come from the chains' explorers through the worker, cached for five minutes. Every key here was public before it landed in a record.