Naive question : Since in the Bode sequence, very basically a geometric progression of orbital diameters, The next orbit out is the same distance as the planet to its Lagrangian point 3. and Lagrangian points are areas where matter is fond of congregating, is the doubling (2R) of planetary orbits just another expression of Lagrange's seminal work? perhaps Starting with Jupiter working outward and inwardly, L3 distance projected into the pre -planetary disk? Lagrangian Point 3 projected Orbits? If you don't know whether to laugh or cry, one way or another, you read it first on SF. and move it where it belongs please. LP3O "law": The orbit sizes of adjoining planets are [almost always *] equal to their distance from their L3 position.** * except when it equal to 1/2 distance to LP3 or R. (see Neptune). and below Venus if orbit radius would be < .3 AU. ** at least in the Solar system. In other words. Once a large body starts to form in the star's disk, the following accretions will fall into the L3, or R distance value. There might be still more grains of truth to glean in Lagrange's grange = french for grenier, silo, barn.