Question

if f(n) = n, we can find solution of this problem in *​

Answer 1

Answer:

N=5

since 5 is an odd prime number

N=4

4 can be written as 2×2 , hence f(2) +f(2)=4

N=20

20 can be written as f(4)+f(5)and f(4) can be written as f(2)+f(2) which is 4