Components octave scaling, how to calculate new values?

Hello, I have an oscillator circuit where it has a 100pF capacitor and osxillates on 7MHz.
The author states that it can work on 3.5MHz if the capacitor is scaled up by two octaves.

What does it mean and how can I calculate the new value of the capacitor? I am not familiar with octaves.

They mean 4x capacitance value.

Thank you.
So 2 octaves up is 4x.
4 octaves up is 8x or 16x?
I am trying to figure out the scaling formula

Hi,

One octave means: ×2
Two octaves: x4
3: ×8
4: ×16

2^n

Klaus