Binary indicator power spectra for all chromosomes of P. falciparum. The spectra were calculated separately for a) coding and b) non-coding region. The overlapping of the 1/3 peaks results from enlarging the vertical axis scale to allow visualising details of non-1/3 peaks. Vertical dashed lines show the positions corresponding to a) k/18 and b) k/21 frequency multiples. For clarity the curves were shifted vertically by arbitrary amounts.