Wolstenholme prime

Last updated
Wolstenholme prime
Named after Joseph Wolstenholme
Publication year1995 [1]
Author of publicationMcIntosh, R. J.
No. of known terms2
Conjectured no. of termsInfinite
Subsequence of Irregular primes
First terms 16843, 2124679
Largest known term 2124679
OEIS index
  • A088164
  • Wolstenholme primes: primes p such that binomial(2p-1,p-1) == 1 (mod p^4)

In number theory, a Wolstenholme prime is a special type of prime number satisfying a stronger version of Wolstenholme's theorem. Wolstenholme's theorem is a congruence relation satisfied by all prime numbers greater than 3. Wolstenholme primes are named after mathematician Joseph Wolstenholme, who first described this theorem in the 19th century.

Contents

Interest in these primes first arose due to their connection with Fermat's Last Theorem. Wolstenholme primes are also related to other special classes of numbers, studied in the hope to be able to generalize a proof for the truth of the theorem to all positive integers greater than two.

The only two known Wolstenholme primes are 16843 and 2124679 (sequence A088164 in the OEIS ). There are no other Wolstenholme primes less than 109. [2]

Definition

Unsolved problem in mathematics:

Are there any Wolstenholme primes other than 16843 and 2124679?

Wolstenholme prime can be defined in a number of equivalent ways.

Definition via binomial coefficients

A Wolstenholme prime is a prime number p > 7 that satisfies the congruence

where the expression in left-hand side denotes a binomial coefficient. [3] In comparison Wolstenholme's theorem states that for every prime p > 3 the following congruence holds:

Definition via Bernoulli numbers

A Wolstenholme prime is a prime p that divides the numerator of the Bernoulli number Bp−3. [4] [5] [6] The Wolstenholme primes therefore form a subset of the irregular primes.

Definition via irregular pairs

A Wolstenholme prime is a prime p such that (p, p–3) is an irregular pair. [7] [8]

Definition via harmonic numbers

A Wolstenholme prime is a prime p such that [9]

i.e. the numerator of the harmonic number expressed in lowest terms is divisible by p3.

Search and current status

The search for Wolstenholme primes began in the 1960s and continued over the following decades, with the latest results published in 2007. The first Wolstenholme prime 16843 was found in 1964, although it was not explicitly reported at that time. [10] The 1964 discovery was later independently confirmed in the 1970s. This remained the only known example of such a prime for almost 20 years, until the discovery announcement of the second Wolstenholme prime 2124679 in 1993. [11] Up to 1.2×107, no further Wolstenholme primes were found. [12] This was later extended to 2×108 by McIntosh in 1995 [5] and Trevisan & Weber were able to reach 2.5×108. [13] The latest result as of 2007 is that there are only those two Wolstenholme primes up to 109. [14]

Expected number of Wolstenholme primes

It is conjectured that infinitely many Wolstenholme primes exist. It is conjectured that the number of Wolstenholme primes  x is about ln ln x, where ln denotes the natural logarithm. For each prime p  5, the Wolstenholme quotient is defined as

Clearly, p is a Wolstenholme prime if and only if Wp  0 (mod p). Empirically one may assume that the remainders of Wp modulo p are uniformly distributed in the set {0, 1, ..., p–1}. By this reasoning, the probability that the remainder takes on a particular value (e.g., 0) is about 1/p. [5]

See also

Notes

  1. Wolstenholme primes were first described by McIntosh in McIntosh 1995, p. 385
  2. Weisstein, Eric W. "Wolstenholme prime". MathWorld .
  3. Cook, J. D. "Binomial coefficients" . Retrieved 21 December 2010.
  4. Clarke & Jones 2004, p. 553.
  5. 1 2 3 McIntosh 1995, p. 387.
  6. Zhao 2008, p. 25.
  7. Johnson 1975, p. 114.
  8. Buhler et al. 1993, p. 152.
  9. Zhao 2007, p. 18.
  10. Selfridge and Pollack published the first Wolstenholme prime in Selfridge & Pollack 1964 , p. 97 (see McIntosh & Roettger 2007 , p. 2092).
  11. Ribenboim 2004, p. 23.
  12. Zhao 2007, p. 25.
  13. Trevisan & Weber 2001, p. 283–284.
  14. McIntosh & Roettger 2007, p. 2092.

Related Research Articles

Chinese remainder theorem Theorem for solving simultaneous congruences

In number theory, the Chinese remainder theorem states that if one knows the remainders of the Euclidean division of an integer n by several integers, then one can determine uniquely the remainder of the division of n by the product of these integers, under the condition that the divisors are pairwise coprime.

Fermat's little theorem states that if p is a prime number, then for any integer a, the number apa is an integer multiple of p. In the notation of modular arithmetic, this is expressed as

In number theory, Euler's criterion is a formula for determining whether an integer is a quadratic residue modulo a prime. Precisely,

The Fermat primality test is a probabilistic test to determine whether a number is a probable prime.

In number theory, Wilson's theorem states that a natural number n > 1 is a prime number if and only if the product of all the positive integers less than n is one less than a multiple of n. That is, the factorial satisfies

In number theory, a Wieferich prime is a prime number p such that p2 divides 2p − 1 − 1, therefore connecting these primes with Fermat's little theorem, which states that every odd prime p divides 2p − 1 − 1. Wieferich primes were first described by Arthur Wieferich in 1909 in works pertaining to Fermat's Last Theorem, at which time both of Fermat's theorems were already well known to mathematicians.

A Wilson prime, named after English mathematician John Wilson, is a prime number p such that p2 divides (p − 1)! + 1, where "!" denotes the factorial function; compare this with Wilson's theorem, which states that every prime p divides (p − 1)! + 1.

In number theory, a Wall–Sun–Sun prime or Fibonacci–Wieferich prime is a certain kind of prime number which is conjectured to exist, although none are known.

The quadratic sieve algorithm (QS) is an integer factorization algorithm and, in practice, the second fastest method known. It is still the fastest for integers under 100 decimal digits or so, and is considerably simpler than the number field sieve. It is a general-purpose factorization algorithm, meaning that its running time depends solely on the size of the integer to be factored, and not on special structure or properties. It was invented by Carl Pomerance in 1981 as an improvement to Schroeppel's linear sieve.

The Solovay–Strassen primality test, developed by Robert M. Solovay and Volker Strassen in 1977, is a probabilistic test to determine if a number is composite or probably prime. The idea behind the test was discovered by M. M. Artjuhov in 1967 (see Theorem E in the paper). This test has been largely superseded by the Baillie–PSW primality test and the Miller–Rabin primality test, but has great historical importance in showing the practical feasibility of the RSA cryptosystem. The Solovay–Strassen test is essentially an Euler–Jacobi pseudoprime test.

Lucas pseudoprimes and Fibonacci pseudoprimes are composite integers that pass certain tests which all primes and very few composite numbers pass: in this case, criteria relative to some Lucas sequence.

In number theory, the von Staudt–Clausen theorem is a result determining the fractional part of Bernoulli numbers, found independently by Karl von Staudt (1840) and Thomas Clausen (1840).

In number theory the Agoh–Giuga conjecture on the Bernoulli numbers Bk postulates that p is a prime number if and only if

In mathematics, Wolstenholme's theorem states that for a prime number , the congruence

In mathematics, Ramanujan's congruences are some remarkable congruences for the partition function p(n). The mathematician Srinivasa Ramanujan discovered the congruences

In number theory, Lucas's theorem expresses the remainder of division of the binomial coefficient by a prime number p in terms of the base p expansions of the integers m and n.

In number theory, the Fermat quotient of an integer a with respect to an odd prime p is defined as:

In mathematics, the Pocklington–Lehmer primality test is a primality test devised by Henry Cabourn Pocklington and Derrick Henry Lehmer. The test uses a partial factorization of to prove that an integer is prime.

In mathematics, a congruence is an equivalence relation on the integers. The following sections list important or interesting prime-related congruences.

In mathematics, specifically in number theory, Newman's conjecture is a conjecture about the behavior of the partition function modulo any integer. Specifically, it states that for any integers m and r such that , the value of the partition function satisfies the congruence for infinitely many non-negative integers n. It was formulated by mathematician Morris Newman in 1960. It is unsolved as of 2020.

References

Further reading