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Integer part of the Verhulst sequence x(n)=x(n-1)+3*(1-x(n-1))*x(n-1), x(0)=.1.
3

%I #13 Jul 13 2013 12:02:17

%S 0,0,1,0,1,0,1,0,1,0,1,0,0,1,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,1,0,0,1,0,

%T 1,0,1,0,0,1,0,0,1,0,0,0,0,1,0,1,0,0,1,0,1,0,0,0,1,0,0,1,0,0,0,0,1,0,

%U 0,1,0,0,1,0,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,0,0,0,1,0,0,1,0,1,0,0,1,0,0,0

%N Integer part of the Verhulst sequence x(n)=x(n-1)+3*(1-x(n-1))*x(n-1), x(0)=.1.

%C a(n) = floor(A220811(n)/A220812(n)). - _Reinhard Zumkeller_, Dec 22 2012

%D Peitgen, H.-O. and Richter, P. H., The Beauty of Fractals. Springer, 1986, p. 24.

%H Reinhard Zumkeller, <a href="/A051840/b051840.txt">Table of n, a(n) for n = 0..1000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LogisticEquation.html">Logistic Equation</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Logistic_map">Logistic map</a>

%t NestList[ #*(4-3*#)&, 0.1, 103] // Floor (* _Jean-François Alcover_, Jan 16 2013 *)

%o (Haskell)

%o a051840 n = a051840_list !! n

%o a051840_list = map floor vs where

%o vs = iterate (\x -> x * (4 - 3 * x)) 0.1

%o -- _Reinhard Zumkeller_, Dec 22 2012

%K easy,nice,nonn

%O 0,1

%A Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Dec 13 1999

%E Data corrected for n > 37 by _Reinhard Zumkeller_, Dec 22 2012