"Grosjean numbers" have nothing to do with AP, they are interesting numerical patterns on odometers and other mechanical devices discussed by biker/author Doug Grosjean.
The only application I can think of for them would be in lottery and related parimutuel systems where the public might be transfixed by a numerical pattern and this could be played to an advantage. Let's say a 3-digit lottery came up "124," 125", "126", "127" on four consecutive days, on the 5th day there might be so much money on 128 that it would pay to bet every number but.