IMO Shortlist 1981 problem 7
Dodao/la:
arhiva2. travnja 2012. The function
satisfies:
for all non-negative integers
. Find
.
%V0
The function $f(x,y)$ satisfies: $f(0,y)=y+1, f(x+1,0) = f(x,1), f(x+1,y+1)=f(x,f(x+1,y))$ for all non-negative integers $x,y$. Find $f(4,1981)$.
Izvor: Međunarodna matematička olimpijada, shortlist 1981