There are some 2048 possible interval arrays spanning one octave starting from a given note. Some of these are labeled arpeggios and others make up scales. The most numerous are the hexatonic and heptatonic scales with 462 types each. Next come pentatonic and octotonic with 330 varieties of each. For arrays with 4 or 9 notes the possibilities come down to 165 each. To complete the list there are 55 arrays with 3 or 10 notes, just 11 possible arrays with 11 or 2 notes and 1 each for that single lonely tonic, or the whole chromatic scale. Here I have tweaked the odds to give you something useful to play, when you click on the image below: