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 A239552 Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-2,...,2}. 2

%I

%S 1,1,1,2,4,7,11,18,32,53,89,152,255,431,733,1243,2111,3583,6087,10342,

%T 17564,29845,50704,86150,146382,248716,422618,718091,1220156,2073272,

%U 3522846,5985967,10171232,17282786,29366645,49899299,84788109,144070585,244802450

%N Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-2,...,2}.

%H Alois P. Heinz, <a href="/A239552/b239552.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) ~ c * d^n, where d = 1.6991842071646453928920987915033839182675484195426953647249305754952..., c = 0.4361924842463814839782496098129122542027259655263562779280217228428... . - _Vaclav Kotesovec_, Aug 28 2014

%e a(5) = 7: [1,1,1,1,1], [1,1,1,2], [1,1,2,1], [1,1,3], [1,2,1,1], [1,2,2], [1,4].

%e a(6) = 11: [1,1,1,1,1,1], [1,1,1,1,2], [1,1,1,2,1], [1,1,1,3], [1,1,2,1,1], [1,1,2,2], [1,2,1,1,1], [1,2,1,2], [1,2,2,1], [1,2,3], [1,5].

%Y Column k=2 of A239550.

%K nonn

%O 0,4

%A _Alois P. Heinz_, Mar 21 2014

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Last modified September 19 20:02 EDT 2020. Contains 337182 sequences. (Running on oeis4.)