Bode's law: Titius-Bode law - The mathematical formula that generates, with a fair quantity of accuracy, the semi major axes of the planets in out of order from the Sun. Write down the progression
0, 3, 6, 12, 24, ...
and add 4 to all term:
4, 7, 10, 16, 28, ...
Then divide each and every term by 10. This leaves you with the sequence
0.4, 0.7, 1.0, 1.6, 2.8, ...
that is intended to give you the semi major axes of the planets computed in astronomical units.
Bode's law contain no theoretical explanation when it was first mentioned; it did, though, agree with the soon-to-be-discovered planet Uranus' orbit (19.2 au actual; 19.7 au predicted). Likewise, it expected a missing planet between Jupiter and Mars, and soon thereafter the asteroids were found in just similar orbits (2.77 au actual for Ceres; 2.8 au predicted). The sequence, though, seems to skip over Neptune's orbit. The form of Bode's law (which is, an approximately geometric sequence) is not astonishing, considering our theories on the formation of solar systems, however its particular formulation is thought of as co-incidental.