W-0019
A superpermutation on 12 symbols, found by Uku Raudvere. It was the first record for n = 12, and held it from Jul 27 until Sep 29, 2026, when W-0026 was 157,188 letters shorter.
- Length
- 522,910,088
- Repeated occurrences
- 0
- Announced
- Jul 27, 2026
0123456789AB0123456789A0B123456789A01B23456789A012B3456789A0123B456789A01234B56789A012345B6789A0123456B789A01234567B89A0…
Windows
| 522,910,077 | windows of 12 consecutive letters | |
| = | 479,001,600 | distinct permutations, all 12! of them |
| + | 0 | repeated occurrences of a permutation |
| + | 43,908,477 | windows that are not permutations |
How it was found
Lifted from the generated n = 11 certificate by Raudvere's recursive constructor (Egan's length minus 1).
Checking
| Program | Source | Result | Time |
|---|---|---|---|
| permcheck | c46d3654 | all 479,001,600 permutations appear | 23 s |
| literal_check | f4687121 | agrees on coverage | 52 s |
Download
Download Detour (.detour) 19.9 kB, or 522.9 MB decoded
# check it yourself
detour decode W-0019.detour - | tr -d '\n' | shasum -a 256
tar xzf checkers-rs-source.tar.gz && cd checkers-rs && cargo build --release --locked
./target/release/classcheck 12 ../W-0019.detour 522910088
./target/release/bitmapcheck 12 ../W-0019.detour 522910088
./target/release/wordhash 12 ../W-0019.detour 522910088
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 = 12 and sync exponent 0. The file has 43,908,383 tokens: 1 START, 1 literal of 1 byte in all, and 43,908,381 deviations. Deviations by weight, from 1 to 12: 0 · 43,908,374 · 7 · 0 · 0 · 0 · 0 · 0 · 0 · 0 · 0 · 0.