PerfectDifferenceSet.lean`

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Credit: The upstream authors and contributors retain credit for the project and mathematics. lean4-explainer only renders their pinned source and adds the separately disclosed explanation layer.

Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1

1 declarations, 0 contain sorry, 0 declared as axioms

Imports (1)

Mathlib.Data.ZMod.Defs

Imported by 1 file

FormalConjecturesForMathlib.lean

def IsPerfectDifferenceSet A perfect difference set modulo n is a set D such that the map (a, b) ↦ a - b from D.offDiag to {x : ZMod n | x ≠ 0} is a bijection line 26 source
Source documentation
A perfect difference set modulo n is a set D such that the map (a, b) ↦ a - b from D.offDiag to {x : ZMod n | x ≠ 0} is a bijection.

standard axioms: Quot.sound, propext what this means
Statement uses: Set, Nat
Proof uses: Set.BijOn, Prod, ZMod, IsPerfectDifferenceSet.match_1, HSub.hSub, Set.offDiag, Set.ofPred, Ne, OfNat.ofNat
15 instances, coercions and auxiliary constants left out.
```
def IsPerfectDifferenceSet (D : Set ℕ) (n : ℕ) : Prop :=
…
```