fact: Definition ball_genball (q: Qpos) (a b: X): genball q a b ↔ R q a b.
imports: CoRN.algebra.RSetoid Arith List CoRN.model.totalorder.QposMinMax CSetoids Qmetric Qring Qinf QnnInf QnonNeg ProductMetric QposInf Qposclasses UniformContinuity MathClasses.implementations.stdlib_rationals stdlib_omissions.Pair stdlib_omissions.Q PointFree MathClasses.interfaces.abstract_algebra MathClasses.theory.setoids MathClasses.theory.products