Fourier decomposition amplitudes and phases of the I-band light curve of the Cepheid in the OGLE LMC562.05.9009 system. The symbols on the Y-axes of the different panels have their usual meaning, and the data for the LMC Cepheids (small dots) come from the OGLE Survey (Soszyński et al. 2008). The light of the stable companion was subtracted from the Cepheid light curve before the analysis. The location of the Cepheid on all panels clearly supports fundamental mode pulsation, in agreement with the radius of the Cepheid derived from our analysis (see the text).