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Research draft

composite number

vr.tr.composite-number · XCT.QTY

Let an agent handle composite numbers mathematically, with factorisation, tests and their role in cryptography.

Thing Registry Cross-cutting context

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent handle composite numbers mathematically, with factorisation, tests and their role in cryptography.

A positive integer greater than 1 that has at least one divisor other than 1 and itself, and so can be factored into smaller primes, such as 4, 6, 9 and RSA numbers.

What it is for: Composite numbers are studied in number theory and are central to factoring-based cryptography.

It can be factor it into primes; test compositeness; study special classes such as pseudoprimes; use hard-to-factor composites in cryptography.

Distinguishing features

Not prime and greater than 1

Unique prime factorisation

Some pass primality tests falsely (pseudoprimes)

Factoring large ones is hard

What it looks like

Numbers; notable composites such as RSA challenge numbers.

How it is recognised

Has a divisor other than 1 and itself

Prime factorisation

Classes such as Carmichael numbers or pseudoprimes

Related models

is a kind of - positive integer

integer

is the complement of - among integers above 1

prime number

is used in - RSA

cryptographic key

is studied by - number theory

mathematics

In practice

Families and kinds

semiprimes such as RSA numbers

pseudoprimes and Carmichael numbers

perfect and unitary perfect numbers

powers of ten

Identifiers

OEIS A002808 composite numbers sequence

Standards and regulation

FIPS 186 key generation rules

Failure modes and hazards

Mistaking a pseudoprime for a prime

Weak composites in cryptography

Also called

RSA numberpseudoprimeunitary perfect numberLucas–Carmichael numberpositive power of tenFibonacci pseudoprimeFermat pseudoprimeLucas pseudoprimestrong pseudoprimeCatalan pseudoprimeproduct of four distinct primesproduct of five distinct primesproduct of six distinct primesGiuga numbersphenic numberantisquare numberUnprimeable numbersSmith numberpseudoperfect numbervampire numberKnödel numberZumkeller numbersemiprimesublime numberPoulet numberBlum integer

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.composite-number

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Definition What makes it composite.

Definition is exact.

Test

Compositeness.

Test

Compositeness.

  1. Is this number composite, by which test? measurement
  2. Is the result certain? boundary

Factors

Factorisation.

Factors

Prime factorisation.

  1. What is its prime factorisation? measurement
  2. How long did factoring take? measurement
Classes Special composites.

Classes have properties.

Class

Semiprime, pseudoprime.

Class

Class membership.

  1. Does it belong to a special class? definition
  2. Which property defines it? definition

Records

Factoring records.

Records

Factoring records.

  1. Which RSA numbers have been factored? provenance
  2. When? provenance
Cryptography Security.

Factoring hardness secures keys.

Keys

RSA moduli.

Keys

Key sizes.

  1. How large must RSA moduli be for current security? boundary
  2. Which guidance applies? provenance

Threats

Quantum computing.

Threats

Threats.

  1. How would quantum computers affect factoring? boundary
  2. What is the migration advice? provenance
Teaching Explaining.

Clear explanations.

Explanation

Concepts.

Explanation

Explaining.

  1. How can composites be explained simply? action
  2. What are common misconceptions? boundary

Computation

Tools.

Computation

Tools.

  1. Which tools factor numbers reliably? definition
  2. What are their limits? boundary

What the second pass must settle

  • Should special classes be separate entries?
  • How should factoring records be tracked?
  • How should quantum threats be described?