pith. sign in
theorem

not_squarefree_fortyfive

proved
show as:
module
IndisputableMonolith.NumberTheory.Primes.RSConstants
domain
NumberTheory
line
133 · github
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plain-language theorem explainer

The integer 45 is not square-free because 9 divides it. Number theorists maintaining the Recognition Science constant anchors would cite this when handling the cycle-45 gap in factorizations. The proof assumes square-freeness, applies the definition at the prime 3 with witness 5, and simplifies to a contradiction.

Claim. The positive integer 45 is not square-free.

background

The RSConstants module assembles small decidable arithmetic facts about integers such as 8, 45, 360 and 840 that recur across the reality repo. These facts keep later bridge lemmas readable by avoiding repeated arithmetic. Square-freeness is the property that no prime square divides the integer; the present theorem records the elementary observation that 45 = 3² · 5 fails this property.

proof idea

The proof assumes Squarefree 45. It applies the assumption to the prime 3 together with the witness 5 (from 45 = 9 · 5) and simplifies to reach a contradiction.

why it matters

This fact anchors the factorization of 45 inside the RS constants file and supports the sibling lemma fortyfive_eq_three_sq_mul_five. It ensures downstream lemmas that reference the cycle-45 gap correctly track the repeated factor of 3. No parent theorem or open question is touched.

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