## Missouri Journal of Mathematical Sciences

### On Williams Numbers with Three Prime Factors

#### Abstract

Let $a\in \mathbb{Z}\setminus \{0\}$. A positive squarefree integer $N$ is said to be an $a$-Korselt number ($K_{a}$-number, for short) if $N\neq a$ and $p-a$ divides $N-a$ for each prime divisor $p$ of $N$. By an $a$-Williams number ($W_{a}$-number, for short) we mean a positive integer which is both an $a$-Korselt number and $(-a)$-Korselt number. This paper proves that for each $a$ there are only finitely many $W_{a}$-numbers with exactly three prime factors, as conjectured in 2010 by Bouallegue-Echi-Pinch.

#### Article information

Source
Missouri J. Math. Sci., Volume 25, Issue 2 (2013), 134-152.

Dates
First available in Project Euclid: 12 November 2013

https://projecteuclid.org/euclid.mjms/1384266199

Digital Object Identifier
doi:10.35834/mjms/1384266199

Mathematical Reviews number (MathSciNet)
MR3161630

Zentralblatt MATH identifier
1303.11016

Subjects
Secondary: 11Y11: Primality 11A51: Factorization; primality

#### Citation

Al-Rasasi, Ibrahim; Ghanmi, Nejib. On Williams Numbers with Three Prime Factors. Missouri J. Math. Sci. 25 (2013), no. 2, 134--152. doi:10.35834/mjms/1384266199. https://projecteuclid.org/euclid.mjms/1384266199

#### References

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