Five examples of finding single sinusoidal periods in the K2 Praesepe data. Left column: full LC; middle column: LS periodogram; right column: phased LC, with best period (in days) as indicated. Rows, in order: EPIC 211832848/HSHJ197, 211905618/JS708, 211929980/JS391, and 211908928/JS505. These are representatives from a range of brightnesses and periods. Note that in each case the power spectrum indicates unambiguously periodic signals—the peak is so high that little structure other than the peak can be seen in the power spectrum. These LCs are best interpreted as large spots or spot groups rotating into and out of view.