My son has just started learning about number series and has managed to do all of his homework except for two questions that have him and me stumped. To give you some idea of the level he's at most of the questions were simple number series.. eg Find the nth term in 9, 2, -5, -12 to which the answer is -7n+16. The two questions we are stuck on are: 1. The problem statement, all variables and given/known data Q3) What is the equation for the nth term of the series.. 7, 11, 14, 15 Q4) What are the next two number in the series 0, 1, 1, 2, 5, 8, ?, ? 2. Relevant equations None 3. The attempt at a solution Q3) Sorry if the formatting is off.... Original 7 11 14 15 1st Dif 4 3 1 2nd Dif -1 -2 3rd Diff -1 So it might be a cubic quadratic (third level difference -1) but there aren't enough given numbers to be certain and anyway he hasn't covered quadratic series yet let alone cubic quadratic. Q4) Not a clue. Photocopies of the questions were provided so no typos unless the teacher made them. We're missing something but what?