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%I #10 Sep 08 2022 08:45:50
%S 0,0,0,1,1,2,4,7,16,46,174,3311,268446771,401906756202069927727330981
%N a(n) = a(n-1) + a(n-2)*a(n-3) + a(n-4)^a(n-5).
%C First 5 terms are {0,0,0,1,1}; thereafter apply the recurrence. Note that 0^0=1.
%H Vincenzo Librandi, <a href="/A171874/b171874.txt">Table of n, a(n) for n = 0..15</a>
%H R. Munafo, <a href="http://mrob.com/pub/math/seq-accelerate.html">Accelerating Sequences</a>
%o (Magma) I:=[0, 0, 0, 1, 1]; [n le 5 select I[n] else Self(n-1)+Self(n-2)*Self(n-3)+(Self(n-4))^Self(n-5): n in [1..14]]; // _Vincenzo Librandi_, Dec 18 2012
%o (Haskell)
%o import Data.List (zipWith5)
%o a171874 n = a171874_list !! n
%o a171874_list = [0, 0, 0, 1, 1] ++ zipWith5 (\z y x w v -> z + x*y + w^v)
%o (drop 4 a171874_list) (drop 3 a171874_list)
%o (drop 2 a171874_list) (tail a171874_list) a171874_list
%o -- _Reinhard Zumkeller_, Aug 14 2013
%K nonn
%O 0,6
%A _Robert Munafo_, Jan 21 2010
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