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%I #9 Feb 22 2013 21:38:27
%S 1,2,2,4,4,4,4,4,4,4,4,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
%T 8,8,8,8,8,8,8,8,8,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,
%U 16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16
%N a(1)=1 followed by 2^k appearing 2^(2*k-1) times for k>0.
%C Occured when analyzing A056753 to construct a recurrence.
%H R. Zumkeller, <a href="/A164632/b164632.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = f(n,1,1) with f(x,y,z) = if x=1 then z else if y=1 then f(x-1,2*z*z,2*z) else f(x-1,y-1,z).
%o (Haskell)
%o a164632 n = a164632_list !! (n-1)
%o a164632_list = 1 : concatMap (\x -> replicate (2^(2*x-1)) (2^x)) [1..]
%o -- _Reinhard Zumkeller_, Feb 24 2012, Oct 17 2010
%Y Cf. A000079, A004171, A081294, A053644.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Aug 23 2009
%E Typo in formula fixed by _Reinhard Zumkeller_, Oct 16 2010
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