Here's a quick tutorial I put together showing how to make a semi-generative sequence with the Elektron Digitone.

The Digitone is an FM synthesizer, with lots of modulation points, and designed to have a very musical FM implementation. By default, the operator ratios are mostly integer, and you have to go out of your way to make it sound weird. Definitely still possible though!

So since it's very musical, this means the primary carrier oscillator shifts in octaves. We can exploit this with the random LFO, set in Sample and Hold mode. Each note played can shift in plus/minus octaves, as defined by the LFO depth - I've found 3 to be quite pleasing.

With the LFO set up, we can sequence an ostensibly simple melody, and have the random range of octaves on the carrier wave introduce variation! If we want the primary melody back, then shifting the X/Y mix away from the carrier will get us there.

Have fun!