Not really a Fibonacci
version number system since v(n + 1) = v(n) + n + 5, v(-1) = 0. It doesn't depend on v(n - 1), so while it's a recurrence relation it isn't a Fibonacci-type sequence.
The next version should be 5 + 6 + 7 = 18, not 17.
The next version should be 5 + 6 + 7 = 18, not 17.
v(1) = 6
v(2) = 11
v(3) = v(1) + v(2) = 17
In general sequences, especially short ones, can have many ways to be generated, but I imagine this is the one the GP meant.