W. Mlotkowski et R. Szwarc, Nonnegative linearization for polynomials orthogonal with respect to discrete measures, CONSTR APPR, 17(3), 2001, pp. 413-429
We give conditions for the coefficients in three term recurrence relations
implying nonnegative linearization for polynomials orthogonal with respect
to measures supported on convergent sequences of points. The previous metho
ds were unable to cover this case.