Learning from each prior question I've designed. Working toward a standard-style question, though not quite there yet. In the interim, here's a tester..
12, 15, 19, 29, 44, 51, ... ?
Your options are:
Just as haiku follows a set format, I'm working to a set format here. To get from one term to the next, I employ three set mathematical calculations - although in this quiz, the boundary for 'calculation' is not clear. Is it 3? Or is it 4? We'll decide once the solution comes out.