Frobenius pseudoprimes

Frobenius pseudoprimes

The proliferation of probable prime tests in recent years has produced a plethora of definitions with the word “pseudoprime” in them. Examples include pseudoprimes, Euler pseudoprimes, strong pseudoprimes, Lucas pseudoprimes, strong Lucas pseudoprimes, extra strong Lucas pseudoprimes and Perrin pseudoprimes. Though these tests represent a wealth of ideas, they exist as a hodge-podge of definiti...

On the Distributions of Pseudoprimes, Carmichael Numbers, and Strong Pseudoprimes

Building upon the work of Carl Pomerance and others, the central purpose of this discourse is to discuss the distribution of base-2 pseudoprimes, as well as improve upon Pomerance's conjecture regarding the Carmichael number counting function [8]. All conjectured formulas apply to any base b ≥ 2 for x ≥ x0(b). A table of base-2 pseudoprime, 2-strong pseudoprime, and Carmichael number counts up ...

Cipolla Pseudoprimes

We consider the pseudoprimes that M. Cipolla constructed. We call such pseudoprimes Cipolla pseudoprimes. In this paper we find infinitely many Lucas and Lehmer pseudoprimes that are analogous to Cipolla pseudoprimes.

Carmichael numbers and pseudoprimes

We now establish a pleasantly simple description of Carmichael numbers, due to Korselt. First, we need the following notion. Let a and p be coprime (usually, p will be prime, but this is not essential). The order of a modulo p, denoted by ordp(a), is the smallest positive integer m such that a ≡ 1 mod p. Recall [NT4.5]: If ordp(a) = m and r is any integer such that a ≡ 1 mod p, then r is a mult...

Pseudoprimes and Carmichael Numbers