%off nat;
on rounded;




n:=5;


N := 5


operator a,f,ff;



for all ii such that ii<0 or ii>n-1 let a(ii)=0;


for all ii,jj let f(ii)*f(jj)=f(ii+jj);


for all ii let f(ii)*f(ii)=f(ii+ii);


f(0):=1;