PD0006 · conservative definition

IsGCD

g is a common divisor divisible by every common divisor.

Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved. Exact original first-admission records.

Readable signature

IsGCD(g,a,b)

Exact expansion

((exists x. a = g * x) /\ (exists y. b = g * y)) /\ forall d. (exists u. a = d * u) -> (exists v. b = d * v) -> exists w. g = d * w

This node is conservative notation, not a theorem, new axiom, predicate constant, or kernel rule. Its expansion is checked for exact first-order AST equivalence.

Definition neighborhood

Expands using

Used by definitions

none

Used by theorem statements or local proof propositions