Denote the equation f(m+n)2=f(m∣f(n)∣)+f(n2) by P(m,n). P(0,0) implies f(0)2=2f(0), thus f(0)∈{0,2}.
When f(0)=0, P(m,0) implies f(m)=0 for any m∈N0. Since this f satisfies the condition, there is just one possible tuple (f(0),f(1),…,f(2024)) in this case.
We consider the case f(0)=2. P(0,1) implies f(1)2=f(1)+2, thus we have f(1)∈{−1,2}. If f(1)=−1, P(1,1) implies f(2)2=−2 which contradicts f(2)∈Z. Therefore we have f(1)=2. Then P(m,1) and P(m,0) imply that f(m+1)2=f(2m)+2=f(m)2. By induction we have ∣f(m)∣=2 for any m∈N0. Moreover, f(2m)=f(m)2−2=2 holds. On the other hand, P(0,n) implies f(n2)=f(n)2−f(0)=2 for any n∈N0.
Conversely, if we choose f:N0→{−2,2} so that f(n)=2 whenever n is even or square, f satisfies the condition because f(m+n)2=4, f(m∣f(n)∣)=f(2m)=2 and f(n2)=2 for any m,n∈N0. Since there exist 990 integers between 0 to 2024 which are neither even nor square, the number of possible tuples (f(0),f(1),…,f(2024)) in this case is 2990.
Therefore the answer is 2990+1.