## Investigating the behaviour of a recursively defined sequence

### Problem 197

Given is the function f(x) = ⌊230.403243784-x2⌋ × 10-9 ( ⌊ ⌋ is the floor-function),
the sequence un is defined by u0 = -1 and un+1 = f(un).

Find un + un+1 for n = 1012.