We develop a modular geometric structure for integers of the form 6n ± 1, leadingto two exact sieving systems: the Affine Modular Sieve (AMS) and the ModularCircle Sieve (MCS). From the structure of the MCS, we formulate two exclusionmechanisms operating at different levels. The first, the Geometric Factor BoundingTheorem (GFBT), establishes a local, deterministic upper bound on the smaller factorof a composite integer, contingent upon its residue class. The second, the FactorExclusion Theorem (FET), introduces a framework for excluding factor candidatesthrough geometrically induced congruential relations.In addition, we introduce a deterministic factorization procedure derived frommodular geometry, intended as a structural tool rather than an optimization method.An analysis of the associated search domain reveals a structural asymmetry betweenthe classes 6n + 1 and 6n − 1, situating the work within a unified conceptual approachto the geometric exclusion of factors. Finally, we present a case study that illustratesthe local completeness of the exclusion information encoded in the geometric intervals
Luis Gabriel Delgado Rodríguez (Tue,) studied this question.