Superpermutation Almanac
Proved at least
6,746,626,957
Shortest known
6,747,802,319
Gap
1,175,362

The record is W-0075, found by Jakub Halfar on Oct 20, 2026.

The bounds over time

Every verified word

WordLengthFound byDateShorter than the record beforeRepeatsOther windows
W-0075 6,747,802,319 Jakub Halfar Oct 20, 2026 74 1,797,743 518,983,764
W-0068 6,747,802,393 Jakub Halfar Oct 8, 2026 169 1,797,600 518,983,981
W-0067 6,747,802,562 Jakub Halfar Oct 6, 2026 313 1,798,294 518,983,456
W-0065 6,747,802,875 Jakub Halfar Oct 6, 2026 114,042 1,798,297 518,983,766
W-0061 6,747,916,917 Jakub Halfar Oct 5, 2026 504 1,693,443 519,202,662
W-0059 6,747,917,421 Jakub Halfar Oct 5, 2026 43 1,693,434 519,203,175
W-0057 6,747,917,464 Jakub Halfar Oct 5, 2026 34 1,693,435 519,203,217
W-0054 6,747,917,498 Jakub Halfar Oct 5, 2026 472 1,693,434 519,203,252
W-0050 6,747,917,970 Jakub Halfar Oct 4, 2026 88 1,693,436 519,203,722
W-0043 6,747,918,058 Jakub Halfar Oct 3, 2026 8 1,693,436 519,203,810
W-0036 6,747,918,066 Jay Pantone jaypantone Oct 1, 2026 49,732 1,693,436 519,203,818
W-0031 6,747,967,798 Jay Pantone jaypantone Sep 29, 2026 19,328 1,693,440 519,253,546
W-0027 6,747,987,126 Jay Pantone jaypantone Sep 29, 2026 1,580,883 1,693,440 519,272,874
W-0020 6,749,568,009 Uku Raudvere Jul 27, 2026 — 0 522,547,197

Bounds at n = 13

Upper bounds
6,749,568,010Egan's bound, Greg Egan, 2018Paper
6,749,568,009Egan's bound minus one, Uku Raudvere, 2026Lean, kernel-checked
6,748,993,440The 101/120 bound, Jay Pantone jaypantone, 2026Lean, kernel-checked
6,748,116,480The 3/5 bound, Jay Pantone jaypantone, 2026Lean, kernel-checked
6,747,802,319W-0075, the shortest known word, Jakub Halfar, 2026Checked word
1,175,362gap
Lower bounds
6,746,626,957S(13) ≥ 6,746,626,957, Jakub Halfar, 2026Lean, kernel-checked
6,746,626,531Pantone's bound, Jay Pantone jaypantone, 2026Lean, statement reviewed
6,746,615,766Halfar's general bound, Jakub Halfar, 2026Lean, statement reviewed
6,746,553,315Kisic's bound, Marin Kisic and Jakub Halfar, 2026Lean, kernel-checked
6,746,523,219Liu's bound, Xiaolong Liu, 2026Lean, statement reviewed
6,746,243,919The Hunter–Raudvere bound, Zach Hunter and Uku Raudvere, 2026Lean, statement reviewed
6,746,084,362Raudvere's bound, Uku Raudvere, 2026Lean, kernel-checked
6,745,939,2114chan + 1, Robin Houston, 2018Lean proof
6,745,939,210The 4chan bound, Anonymous 4chan poster, Robin Houston, Jay Pantone jaypantone and Vince Vatter, 2011Paper

All bounds, with their formulas