Please help me!! Will Give Medal!!

Find f(5) for this sequence:

f(1) = 2 and f(2) = 5, f(n) = f(1) + f(2) + f(n - 1), for n 2.

f(5) = ______

Question

Please help me!! Will Give Medal!! 

Find f(5) for this sequence:

f(1) = 2 and f(2) = 5, f(n) = f(1) + f(2) + f(n - 1), for n > 2.

f(5) = ______

anonymous · Answer

$$f(1)=2\
f(2)=5\
f(3)=f(1)+f(3)=2+5=7$$ lather rinse repeat

anonymous · Answer

oops typo there, i meant 
$$f(3)=f(1)+f(2)=2+5=7$$

anonymous · Answer

Is that the answer or do I solve that? @satellite73

anonymous · Answer

Would the answer be 13 @satellite73

anonymous · Answer

@Tay111

anonymous · Answer

Unfortunately, i do not remember how to do this.

anonymous · Answer

Its Fine thanks Tho

anonymous · Answer

@amistre64 @Hero  Can you help me please?

amistre64 · Answer

you were given a rule to apply.  what about the rule do you not understand?  or is it the notation that is off putting?