%I #6 Nov 08 2017 19:31:59
%S 1,2,3,5,13,65533
%N Ackermann's function A(n,0).
%H R. G. Wilson v, <a href="/A126333/a126333.pdf">Letter to N. J. A. Sloane, Nov. 1988</a>
%F A(0,n)=1+n, A(m+1,0)=A(m,1), A(m+1;n+1)=A(m,A(m+1,n)).
%Y Cf. A014221, A001695.
%K nonn
%O 0,2
%A Philippe LALLOUET (philip.lallouet(AT)wanadoo.fr), Mar 10 2007