W-0010
A superpermutation on 7 symbols, found by Greg Egan. It beat the previous record, W-0009, by 4 letters, and was the record for n = 7 from Oct 19, 2018 until Feb 1, 2019, when W-0013 was 1 letter shorter.
- Length
- 5,908
- Repeated occurrences
- 0
- Announced
- Oct 19, 2018
012345601234506123405612340651234061523406125340612354061234501623405162340156234105623415062341560234156203415623041562…
Windows
| 5,902 | windows of 7 consecutive letters | |
| = | 5,040 | distinct permutations, all 7! of them |
| + | 0 | repeated occurrences of a permutation |
| + | 862 | windows that are not permutations |
How it was found
From Egan's adaptation of Aaron Williams's Hamiltonian-cycle construction, which gives length n! + (n-1)! + (n-2)! + (n-3)! + n - 3.
Checking
| Program | Source | Result | Time |
|---|---|---|---|
| permcheck | c46d3654 | all 5,040 permutations appear | under 1 s |
| literal_check | f4687121 | agrees on coverage | under 1 s |
Download
Download Detour (.detour) 188 bytes, or 5.9 kB decoded
Download text (.txt) 5.9 kB
# check it yourself
detour decode W-0010.detour - | tr -d '\n' | shasum -a 256
tar xzf checkers-rs-source.tar.gz && cd checkers-rs && cargo build --release --locked
./target/release/classcheck 7 ../W-0010.detour 5908
./target/release/bitmapcheck 7 ../W-0010.detour 5908
./target/release/wordhash 7 ../W-0010.detour 5908
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 = 7 and sync exponent 0. The file has 860 tokens: 1 START, 1 literal of 1 byte in all, and 858 deviations. Deviations by weight, from 1 to 7: 0 · 858 · 0 · 0 · 0 · 0 · 0.