W-0063

A superpermutation on 11 symbols, found by Jakub Halfar. It beat the previous record, W-0052, by 36 letters, and was the record for n = 11 from Oct 6 until Oct 28, 2026, when W-0079 was 30 letters shorter.

Length: 43,930,578
Repeated occurrences: 19,784
Announced: Oct 6, 2026

Begins

0123456789A01234567890A12345678901A23456789012A34567890123A45678901234A56789012345A67890123456A78901234567A89012345678A9…

Windows

	43,930,568	windows of 11 consecutive letters
=	39,916,800	distinct permutations, all 11! of them
+	19,784	repeated occurrences of a permutation
+	3,993,984	windows that are not permutations

How it was found

Pantone's construction on a new selection, which gives far fewer closed trails, chained by an integer programme; Halfar's library kernel-checks HasWord 11 43930578 in Lean.

Checking

Total check time: 2 s, including preparation but not time in the queue.

Program	Source	Result	Time
classcheck	41928cce	all 39,916,800 permutations appear, by rotation class	under 1 s
bitmapcheck	288b3f67	agrees, by Lehmer rank	1 s
wordhash	94925fe4	the SHA-256 of the word and of its mirror	under 1 s

SHA-2568e32c099a248cc1d7ab7398865754b91b62de66259e4fe06db5b2f2c6d0ae840 Compilerrustc 1.89.0 (29483883e 2025-08-04)

Download

Download Detour (.detour) 8.6 kB, or 43.9 MB decoded

Decode to text

# check it yourself
detour decode W-0063.detour - | tr -d '\n' | shasum -a 256
tar xzf checkers-rs-source.tar.gz && cd checkers-rs && cargo build --release --locked
./target/release/classcheck 11 ../W-0063.detour 43930578
./target/release/bitmapcheck 11 ../W-0063.detour 43930578
./target/release/wordhash 11 ../W-0063.detour 43930578

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 = 11 and sync exponent 0. The file has 513,663 tokens: 1 START, 1 literal of 1 byte in all, and 513,661 deviations. Deviations by weight, from 1 to 11: 19,784 · 136,694 · 356,969 · 14 · 70 · 41 · 22 · 22 · 32 · 13 · 0.