Remarks on multi-frequency oscillations in symmetrically coupled escalators

Coupled nonlinear oscillators that lead to oscillations where one oscillator oscillates with frequencies that are integer multiples of all other oscillators are analyzed. It is shown that oscillations with multiple frequencies < n occur in systems of n identical and symmetrically coupled oscillators (S-n symmetry). Solutions with n-fold frequencies occur for systems of n identical oscillators symmetrically coupled to each other and to one additional different oscillator. (C) 1999 Elsevier Science B.V.