2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/98339It is shown that most possibly truncated power series rings admit uncountably many filtered lambda-ring structures. The question of how many of these filtered lambda-ring structures are topologically realizable by the K-theory of torsionfree spaces is also considered for truncated polynomial rings.Algebraic TopologyCommutative AlgebraRings and Algebras55N15; 55S25; 13D15text