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Wolstenholme Prime

Reference: Wikipedia

namespace WolstenholmePrime

Wolstenholme's theorem states that any prime $p > 3$ satisfies $\binom{2p-1}{p-1} \equiv 1 (\pmod{p^3})$.

Formal proof linked here provided by AlphaProof. Reference: Wikipedia

@[category textbook, AMS 11, formal_proof using formal_conjectures at "https://github.com/mo271/formal-conjectures/blob/d833ed31d82693f10bed7a4c9ac329545b556a03/FormalConjectures/Wikipedia/WolstenholmePrime.lean#L34"] theorem declaration uses 'sorry'wolstenholme_theorem (p : ) (h : p > 3) (hp : Nat.Prime p) : (2 * p - 1).choose (p - 1) 1 [MOD p ^ 3] := p:h:p > 3hp:Nat.Prime p(2 * p - 1).choose (p - 1) 1 [MOD p ^ 3] All goals completed! 🐙

A prime $p > 7$ is called a Wolstenholme prime if $\binom{2p-1}{p-1} \equiv 1 (\pmod{p^4})$.

def IsWolstenholmePrime (p : ) : Prop := p > 7 p.Prime (2 * p - 1).choose (p - 1) 1 [MOD p ^ 4]

Two known Wolstenholme primes: 16843 and 2124679.

Formal proof linked here provided by AlphaProof

@[category test, AMS 11, formal_proof using formal_conjectures at "https://github.com/mo271/formal-conjectures/blob/d833ed31d82693f10bed7a4c9ac329545b556a03/FormalConjectures/Wikipedia/WolstenholmePrime.lean#L73"] theorem wolstenholme_prime_16483 : IsWolstenholmePrime 16843 := IsWolstenholmePrime 16843 16843 > 7 Nat.Prime 16843 (2 * 16843 - 1).choose (16843 - 1) % 16843 ^ 4 = 1 % 16843 ^ 4 refine 16843 > 7 All goals completed! 🐙, Nat.Prime 16843 All goals completed! 🐙, ?_ All goals completed! 🐙 @[category test, AMS 11] theorem wolstenholme_prime_2124679 : IsWolstenholmePrime 2124679 := IsWolstenholmePrime 2124679 2124679 > 7 Nat.Prime 2124679 (2 * 2124679 - 1).choose (2124679 - 1) % 2124679 ^ 4 = 1 % 2124679 ^ 4 refine 2124679 > 7 All goals completed! 🐙, Nat.Prime 2124679 All goals completed! 🐙, ?_ All goals completed! 🐙

Equivalently, a prime $p > 7$ is a Wolstenholme prime if it divides the numerator of the Bernoulli number $B_{p-3}$.

@[category textbook, AMS 11] theorem declaration uses 'sorry'wolstenholme_bernoulli (p : ) : IsWolstenholmePrime p (p > 7) Nat.Prime p p (bernoulli' (p - 3)).num := p:IsWolstenholmePrime p p > 7 Nat.Prime p p (bernoulli' (p - 3)).num All goals completed! 🐙

Another equivalent definition is that a prime $p > 7$ is a Wolstenholme prime if it $p^3$ divides the numerator of the harmonic number $H_{p-1}$.

@[category textbook, AMS 11] theorem declaration uses 'sorry'wolstenholme_harmonic (p : ) : IsWolstenholmePrime p (p > 7) Nat.Prime p (p ^ 3) (harmonic (p - 1)).num := p:IsWolstenholmePrime p p > 7 Nat.Prime p (p ^ 3) (harmonic (p - 1)).num All goals completed! 🐙

It is conjectured that there are infinitely many Wolstenholme primes.

Reference: Wikipedia

@[category research open, AMS 11] theorem declaration uses 'sorry'wolstenholme_prime_infinite : {p : | IsWolstenholmePrime p}.Infinite := {p | IsWolstenholmePrime p}.Infinite All goals completed! 🐙 end WolstenholmePrime