W-0011
A superpermutation on 8 symbols, found by Greg Egan. It was the first record for n = 8, and held it from Oct 19, 2018 until Jul 26, 2026, when W-0015 was 1 letter shorter.
- Length
- 46,205
- Repeated occurrences
- 0
- Announced
- Oct 19, 2018
Begins
012345670123456071234506712345076123450716234507126345071236450712346507123456017234506172345016723451067234516072345167…
Windows
| 46,198 | windows of 8 consecutive letters | |
| = | 40,320 | distinct permutations, all 8! of them |
| + | 0 | repeated occurrences of a permutation |
| + | 5,878 | windows that are not permutations |
How it was found
Egan's adaptation of the Williams construction at n = 8.
Checking
| Program | Source | Result | Time |
|---|---|---|---|
| permcheck | c46d3654 | all 40,320 permutations appear | under 1 s |
| literal_check | f4687121 | agrees on coverage | under 1 s |
SHA-256ffdb75e71732f47527961e1d062f95040973d9c9f9d9d02b43d2257b32a8d190
Compilerg++ (Debian 14.2.0-19) 14.2.0
Download
Download Detour (.detour) 244 bytes, or 46.2 kB decoded
Download text (.txt) 46.2 kB
# check it yourself
detour decode W-0011.detour - | tr -d '\n' | shasum -a 256
tar xzf checkers-rs-source.tar.gz && cd checkers-rs && cargo build --release --locked
./target/release/classcheck 8 ../W-0011.detour 46205
./target/release/bitmapcheck 8 ../W-0011.detour 46205
./target/release/wordhash 8 ../W-0011.detour 46205
Decoding needs detour; see the Detour format for how to build and install it. The checkers are in checkers-rs-source.tar.gz, which needs Rust 1.89 or later; each one decodes the file itself, so the word is never written out.
The file's header gives n = 8 and sync exponent 0. The file has 5,875 tokens: 1 START, 1 literal of 1 byte in all, and 5,873 deviations. Deviations by weight, from 1 to 8: 0 · 5,873 · 0 · 0 · 0 · 0 · 0 · 0.