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• Numbers
• ACL2-built-ins

Numerator

Dividend of a ratio in lowest terms

Completion Axiom (completion-of-numerator):

(equal (numerator x)
       (if (rationalp x)
           (numerator x)
         0))

Guard for (numerator x):

(rationalp x)

Subtopics

More-rational-identities

Rules about numerator and denominator in the arithmetic/rationals book.

Basic-rational-identities

Basic cancellation rules for numerator and denominator terms.