lotterypuzzle atlas

Bitcoin Puzzle record

Bitcoin Puzzle #75

found · spent

7.5 BTC nominal274 candidate keys

Where it sits on the line

Puzzles #63–#87: search work One column per puzzle; height is the base-2 logarithm of the search steps. Puzzle #75 is highlighted. The line sits at 2^69. #63 · 2^62 #64 · 2^63 #65 · 2^33 #66 · 2^65 #67 · 2^66 #68 · 2^67 #69 · 2^68 #70 · 2^35.5 #71 · 2^70 #72 · 2^71 #73 · 2^72 #74 · 2^73 #75 · 2^38 #76 · 2^75 #77 · 2^76 #78 · 2^77 #79 · 2^78 #80 · 2^40.5 #81 · 2^80 #82 · 2^81 #83 · 2^82 #84 · 2^83 #85 · 2^43 #86 · 2^85 #87 · 2^86
  • found
  • open · address only
  • open · public key on chain
  • the line · 269

This puzzle needs about 238 search steps — below the line (269).

Every puzzle below the line has been found.

Model: kangaroo. The public key has been on chain since 2019, so the square-root shortcut applies: about 2 × 2(N−1)/2 group operations.

How the work is estimated

Record

P2PKH address
1J36UjUByGroXcCvmj13U6uwaVv9caEeAt
mempool.space Blockstream
Known public key
03726b574f193e374686d8e12bc6e4142adeb06770e0a2856f5e4ad89f66044755
HASH160
badf8b0d34289e679ec65c6c61d3a974353be5cf
Search class
historical
The output has been spent. Dates and labels are catalog attributions, not audited identities.
Candidate interval
274 → 275 − 1
start0x4000000000000000000
end0x7ffffffffffffffffff
Interval size18889465931478580854784 scalars. Exact BigInt bounds, not a floating estimate.

Snapshot 2 Oct 2026. The reward is the catalog's nominal allocation (N × 0.1 convention from 2023-04-16; earlier spends predate it), not a live balance. A key that matches the address proves the math, not that the coins are still there: check an explorer. Missing fields are omitted, not invented.

Solution record

Catalog date
Block
580160
Evidence
On-chain
Catalog label
pikachunakapika
A spend proves key control, not a forum identity.
Transactions
mempool.space tx Solve transaction · Blockstream

Where the key sat in its range

Published position in range: 19.32%

0% · start of rangeend of range · 100%

Published historical scalar (already public)

This hex scalar is already in the public puzzle corpus. It is historical evidence, not a live key to import. This page does not produce WIF and does not handle secret material.

0000000000000000000000000000000000000000000004c5ce114686a1336e07

Mentioned in the atlas

Where #75 comes up in the room pages. rooms 1 · mentions 1

Scale

Method

Historical record. Method notes for open puzzles live on the method page.