quizchain/15

Solved on 2019-04-10 after 12h 30m, key derived from the published recipe. 0.007 BTC on Bitcoin.

Story

What the post asked, what the answer turned out to be, and what the chain says happened. The record below holds the data.

The hash app reset itself

A sentence from the whitepaper, minus some letters. Which letters? The ones in the author's handle: a, o and i. So The lngest chn nt nly serves s prf f the sequence f the events wtnessed ZNb, with a space before the link this time.

The post said SHA-256. Then came the emergency update. The author had restarted the hashing app, it woke up on MD5, and nobody noticed. The funded key is the MD5 one.

An MD5 hash is 16 bytes, so the seed has 12 words instead of 24. Everything else is the same. And that accident stuck: from here on the whole chain runs on MD5.

IDquizchain/1515 / 772019-04-09 → 2019-04-10

Puzzle / quizchain

15

bitcoinp2pkh solved

Record

bitcoinPuzzle({
  address: p2pkh("112Gm9cAaaLS…AGwiM3mZ", "003d929e87cc…4450447b"),
  status: Status.Solved,
  key: wif("KwszAWYYFHvE…XRbNQzF3").entropy("d552ee8c4921…831554fb", source("https://www.…lock_15/")).derived(),
})

Prize: 0.007 BTC
Key material: wif, derived from the recipe
Verification: verified
Solved: 2019-04-10 · 12h 30m

tx 2

Trail: Explorerblockstream.info; Sourcereddit.com/r/bitcoinpuzzles/comments/bb7q8r/easy_7_mbtc_quizchain_block_15; Tryquizchain/15 in the playground

Address: 112Gm9cAaaLSPLBcRDaCyoyrUwAGwiM3mZ

hash160 003d929e87cc54e232047622235f33e74450447b

Balance

asking the explorer

Key

public key · compressed: 02e75292ab0b96d719b0c6bbf13da054196d6fcdee64df0c075528a7292bfcfd6c
WIF: KwszAWYYFHvEsfayfwP2YvvSFJ9gd6UFKJ5FjritPRJkXRbNQzF3
entropy hash: d552ee8c492129a28e5d7d18831554fb
entropy source: MD5 of the sentence without its a, o and i, a space and the last three characters of the block 14 key

Transactions

funding2019-04-090.007 BTC28c827328e…200342
claim2019-04-100.00669472 BTC98dec91af8…6fb25e

Hints

undated
officialThe longest chain not only serves as proof of the sequence of the events witnessed
Sourcereddit.com/r/bitcoinpuzzles/comments/bb7q8r/easy_7_mbtc_quizchain_block_15
Published answer
The lngest chn nt nly serves s prf f the sequence f the events wtnessed ZNb
Sourcereddit.com/r/bitcoinpuzzles/comments/bb7q8r/easy_7_mbtc_quizchain_block_15
undated
officialRemove certain letters from that sentence for the solution, then append the last three digits of the private key of the previous block, with a space between the solution and the linking three digits.
Sourcereddit.com/r/bitcoinpuzzles/comments/bb7q8r/easy_7_mbtc_quizchain_block_15
undated
officialEmergency update: I found another way to screw this up. Delivery on this one works only if you do the hash with MD5 algorithm. I restarted the hashing app and did not notice that it reset to MD5...
Sourcereddit.com/r/bitcoinpuzzles/comments/bb7q8r/easy_7_mbtc_quizchain_block_15