Abstract

Given the sequences of real numbers (?i)1n;, (?i)1n-1, satisfying the interlacing property ?i < ?i < ?i+1, 1 ? i ? n -1, we present a new numerical procedure to construct a spring-mass system with eigenvalues (Aj)™, where the interlaced spectrum (?i)1n-1 corresponds to the modified system whose mass mr+1, 1 ? r ? n -2, is fixed. The method, which is a modification of the fast orthogonal reduction technique, appears to be computationally less expensive than other in the literature.