%I #24 May 13 2019 15:56:11
%S 1,2,3,5,11,37,181,1361,13927,183871,3005533,59045717
%N Ludic recurrence: Iterates of f(n) = A003309(n+1) starting from n=1.
%H Donovan Johnson, <a href="/A255420/a255420.txt">Ludic numbers computed up to A003309(1236290) = 23000711</a>
%F a(0) = 1; for n >= 1: a(n) = A003309(1+a(n-1)).
%F Other identities. For all n >= 0:
%F a(n) = A237126(A000225(n+1)).
%F a(n) = A255421(A007097(n)).
%o (Scheme, with memoization-macro definec)
%o (definec (A255420 n) (if (zero? n) 1 (A003309 (+ 1 (A255420 (- n 1))))))
%o (Haskell)
%o a255420 n = a255420_list !! n
%o a255420_list = iterate (a003309 . (+ 1)) 1
%o -- _Reinhard Zumkeller_, Feb 25 2015
%Y Cf. A000225, A003309, A007097, A237126, A255421.
%K nonn,more
%O 0,2
%A _Antti Karttunen_, Feb 23 2015