Answer:
p(n) = 4·6^(n-1)
Explanation:
The sequence is a geometric sequence with first term 4 and common ratio ...
24/4 = 144/24 = 864/144 = 6
The general term of a geometric sequence with first term a1 and common ratio r is ...
an = a1·r^(n-1)
Filling in the values for this sequence, we have the general term ...
an = 4·6^(n-1)
Putting this in functional form, we have the population p as a function of year n ...
p(n) = 4·6^(n-1)