Raudvere's bound
For every n ≥ 5, S(n) \ge n! + (n-1)! + (n-2)! + n - 3 + \left\lceil \frac{(n-3)! - 1}{2n-1} \right\rceil
- Holds for
- n ≥ 5
- Announced
- Jul 18, 2026
- Proof
- Lean proof
- Coefficient of (n−3)!
- 0
By Uku Raudvere.
Values
| n | At least |
|---|---|
| 5 | 153 |
| 6 | 868 |
| 7 | 5,886 |
| 8 | 46,093 |
| 9 | 408,289 |
| 10 | 4,032,273 |
| 11 | 43,910,408 |
| 12 | 522,562,987 |
| 13 | 6,746,084,362 |
| 14 | 93,885,792,011 |
Evidence
-
Lean proof, kernel-checked
github.com/urdvr/superperm-coeff2
Commit
12acadf0069dd4098a6cacec2dff21b6c8096a18Lean 4 formalization and PDF; Miles Gould confirmed it compiles with only the standard axioms (2026-07-23)
Historical proof checks
These checks cover the bound’s mathematical statement. The paper and source notes are for citation.
kernel-checked
LowerBoundFrom 5 (.add (.sub (.add (.add (.add (.fact 0) (.fact 1)) (.fact 2)) (.var)) (.const 3)) (.div (.sub (.fact 3) (.const 1)) (.sub (.mul (.const 2) (.var)) (.const 1))))
Original job: historical-20261024-144910-8be0622c-raudvere-headline. Original policy: 900414d5499e49fa450a3d19e46083d07c10a485ebbccaf2762c9866715669e4.
Linking lemma written by the Almanac.