quizchain/16

Solved on 2019-04-10 after 5h 56m, 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.

An illegal number

"40 is an illegal number. Fix it." Impossible without the Twitter feed, the post says, and it's right.

The author's 16th Twitter follower is HE4OBEK. That O is illegal in a Bitcoin address, because it looks like a zero. Make it lowercase and the string is HE4oBEK zF3.

This one got hashed with MD5 too, also by accident. After that the author gave up and made MD5 the rule.

IDquizchain/1616 / 772019-04-09 → 2019-04-10

Puzzle / quizchain

16

bitcoinp2pkh solved

Record

bitcoinPuzzle({
  address: p2pkh("12jpR4kuvZwY…ekFYtent", "13112d185509…e8cd8a6e"),
  status: Status.Solved,
  key: wif("KzuMwz6Arizi…wu91FdfP").entropy("3b28447d7c77…49a75c13", source("https://www.…lock_16/")).derived(),
})

Prize: 0.007 BTC
Key material: wif, derived from the recipe
Verification: verified
Solved: 2019-04-10 · 5h 56m

tx 2

Trail: Explorerblockstream.info; Sourcereddit.com/r/bitcoinpuzzles/comments/bbeuye/medium_7_mbtc_quizchain_block_16; Tryquizchain/16 in the playground

Address: 12jpR4kuvZwYqyEFAwEVPq3KKgekFYtent

hash160 13112d185509b2f3e7bee0a6768edd92e8cd8a6e

Balance

asking the explorer

Key

public key · compressed: 03b5242f46392c5161149181ff153be661d559487ce77422f9c5d89dccdd65a0a6
WIF: KzuMwz6AriziBq1R5HiYxPzk9f3WzEQ7QyWVhAr8pn8Dwu91FdfP
entropy hash: 3b28447d7c7713c4f1477bca49a75c13
entropy source: MD5 of the fixed handle, a space and the last three characters of the block 15 key

Transactions

funding2019-04-090.007 BTC602f53a24f…32968c
claim2019-04-100.00679629 BTCb909c46f87…87825c

Hints

undated
officialThe question for block 16: 40 is an illegal number. Fix it. Format for the answer: [solution] [linking three digits from block 15]. Exactly one space between solution and chain link.
Sourcereddit.com/r/bitcoinpuzzles/comments/bbeuye/medium_7_mbtc_quizchain_block_16
Published answer
Solution was derived from the handle name of my 16th follower at the Twitter feed, which is HE4OBEK. The "4O" in the middle is illegal in the Bitcoin address space, since people may be unable to distinguish "0" from "O". To fix it, replace it with lowercase o, for a solution string "HE4oBEK".
Sourcereddit.com/r/bitcoinpuzzles/comments/bbeuye/medium_7_mbtc_quizchain_block_16
undated
officialUpdate: Double-checking revealed that this block also was hashed with MD5.
Sourcereddit.com/r/bitcoinpuzzles/comments/bbeuye/medium_7_mbtc_quizchain_block_16