1. ‘If f(n) is the number of rabbits born in year n, Initial= f(0)=c), f(1)=c1, f(2)=c2
‘f(n)=f(n-1)+f(n-2)+f(n-3)


2. f=proc(n, p1, p2, c0, c1, c2) option remember: 
If n=0 then
c0:
elif n=1then
c1: 
elif n=2 then
C2:
else 
expand(p1*f(n-1, p1, p2, p3, c0, c1, c2)+p2*f(n-2, p1, p2, p3, c0, c1, c2)+p3*f(n-3, p1, p2, p3, c0, c1, c2));
fi:
end:
seq(f(i, 0.3, 0.3, 0.4, 1, 1, 1), i=1000)


3. p1= 0.3, p2=0.3, p3=0.4
These numbers are stable as is, increasing or decreasing them at all would lead to explosion and decay, respectively.