%I #5 Dec 29 2023 13:22:29
%S 0,1,40,2674398,39044429911904441284800,
%T 10934377152170553993439479038404269881062854488806451946716107868799042109068
%N f(f(n+1))-f(f(n)), where f() = Catalan() = A000108.
%K nonn
%O 0,3
%A _N. J. A. Sloane_, Nov 12 2005