This work investigates the set of roots of polynomials whose integer coefficients are restricted to lie within (−n, n), providing new insights into their distribution. We show that the closure of this root set coincides with the connectedness locus Mn for n-ary collinear fractals E(c, n). The locus is characterized by the condition c ∈ Mn if and only if 2c ∈ E(c, 2n − 1). We introduce a geometric inverse-iteration algorithm to certify points in Mn and reveal its dense internal structure. This resolves an open problem on the density of Mn (a generalization of Bandt’s conjecture, proved earlier for n = 2 by Calegari, Koch & Walker and for n ≥ 21 in our prior work). The algorithm defines level sets Ωₖ(n) within the interior of Mn, quantifying its density and uncovering a rich combinatorial organization. We discuss how roots of specific integer polynomials act as structural centers inside Mn, and we examine special algebraic integers with |c| = √n (linked to fractal reptiles and planar self-affine tiles) in relation to the boundary of Mn and dynamically significant regions. Altogether, the results shed light on the interplay between the dynamics of 2c, the topology and geometry of the attractors E(c, n) and E(c, 2n − 1), and the algebraic nature of Mn. An interactive demonstration is available at https://www.complextrees.com/collinear.