Multiples of a week show up in orbital periods
Now that so many moons have been discovered around the other planets there is quite a decent sample, when included with the planets, to look for any tendency to quantisation or periodicity.
The method used is by Kotov. Test values are used to find values that are most nearly multiples or fractions of the values known. The Y-axis shows how well the data fit to the test value. In this graph, test values from 10 to 1000 days are used and show that moons and planets prefer to orbit in multiples or fractions of values near 14, 28, 84 and 252 days and others. Note that these periods are 2, 4, 12 and 36 weeks, a nice set of harmonics.
It seems that an underlying 7 day period pervades the solar system.