What is the next 2 in the sequence 4 6 9 13.5?

Answer 1

The next two can be anything you want them to be (as a formula can be found which matches the sequence so far and gives you any two numbers you want).

However, the simplest formula is probably "the next term is the current term multiplied by 1.5" giving the next two as 20.25 and 30.375

The formula for the nth term is given by t(n) = 4×1.5^(n-1) for n = 1, 2, 3, ...