Some values for Ackermann's function: n m ACK(n m) ------------------------------------------------------- 1 1 3 1 2 4 2 1 5 2 2 7 2 3 9 3 2 29 3 3 61 3 4 stack overflow
ack(0,M,R):- R is M+1,!. ack(N,0,R):- R1 is N-1,ack(R1,1,R). ack(N,m,R):- N1 is N-1,M1 is M-1,ack(N,M1,R1),ack(N1,R1,R).