Superpermutation Almanac

n = 13

W-0059

A superpermutation on 13 symbols, found by Jakub Halfar. It beat the previous record, W-0057, by 43 letters, and was the record for n = 13 on Oct 5, 2026, when W-0061 was 504 letters shorter.

Length
6,747,917,421
Repeated occurrences
1,693,434
Announced
Oct 5, 2026
Begins 0123456789ABC0123456789AB0C123456789AB01C23456789AB012C3456789AB0123C456789AB01234C56789AB012345C6789AB0123456C789AB0123…

Windows

6,747,917,409windows of 13 consecutive letters
=6,227,020,800distinct permutations, all 13! of them
+1,693,434repeated occurrences of a permutation
+519,203,175windows that are not permutations

How it was found

Loop moves and relocation in turn, from the 6,747,917,498 word.

Checking

Total check time: 1 min 51 s, including preparation but not time in the queue.

ProgramSourceResultTime
classcheck41928cceall 6,227,020,800 permutations appear, by rotation class43 s
bitmapcheck288b3f67agrees, by Lehmer rank31 s
wordhash94925fe4the SHA-256 of the word and of its mirror36 s
SHA-256e7f86279a20c36d29bcddea1e507681043404e802f1ac03d2e250ddd27fe8316 Compilerrustc 1.89.0 (29483883e 2025-08-04)

Download

Download Detour (.detour) 314.5 kB, or 6.7 GB decoded

Decode to text

# check it yourself
detour decode W-0059.detour - | tr -d '\n' | shasum -a 256
tar xzf checkers-rs-source.tar.gz && cd checkers-rs && cargo build --release --locked
./target/release/classcheck 13 ../W-0059.detour 6747917421
./target/release/bitmapcheck 13 ../W-0059.detour 6747917421
./target/release/wordhash 13 ../W-0059.detour 6747917421

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 = 13 and sync exponent 0. The file has 54,124,749 tokens: 1 START, 1 literal of 1 byte in all, and 54,124,747 deviations. Deviations by weight, from 1 to 13: 1,693,434 · 15,240,113 · 37,188,504 · 975 · 472 · 371 · 439 · 199 · 62 · 69 · 63 · 42 · 4.