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%I #13 Jul 20 2021 03:27:21
%S 0,1,2,9,730,389017001,58871587162270593034051002,
%T 204040901322752673844230437877671861543858084850895762746141813554591014612009
%N a(n) = a(n-1)^3 + 1 with a(0) = 0.
%C Number of ternary trees of height less than n.
%C The rightmost digits cycle (0, 1, 2, 9, 0, 1, 2, 9, ...).
%H Michael De Vlieger, <a href="/A135361/b135361.txt">Table of n, a(n) for n = 0..9</a>
%H Robin Lamarche-Perrin, <a href="https://arxiv.org/abs/1807.06874">An Information-theoretic Framework for the Lossy Compression of Link Streams</a>, arXiv:1807.06874 [cs.DS], 2018.
%H C. Lenormand, <a href="/A003095/a003095.pdf">Arbres et permutations, 1.2: Magmas et Arborescences</a>, pp. 55, 57.
%F a(n) is asymptotic to c^(3^n) where c=1.0847999710783722816939038440390528005339362697...
%t Nest[Append[#, #[[-1]]^3 + 1] &, {0}, 7] (* _Michael De Vlieger_, Oct 24 2018 *)
%o (Sage)
%o def a(n): return 0 if (n==0) else a(n-1)^3 + 1
%o [a(n) for n in (0..9)] # _G. C. Greubel_, Jul 19 2021
%Y Cf. A003095, A008322, A119731.
%K easy,nonn
%O 0,3
%A _Gerald McGarvey_, Dec 08 2007
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