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a(n)=(a(n-1)^3*a(n-2)^2+1)/a(n-3) with a(0)=a(1)=a(2)=1.
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%I #18 Mar 19 2017 08:46:43

%S 1,1,1,2,9,2917,1005227383127,

%T 960336157066554685167071011848947459782832

%N a(n)=(a(n-1)^3*a(n-2)^2+1)/a(n-3) with a(0)=a(1)=a(2)=1.

%C This is the case a=2, b=3, y(0)=y(1)=y(2)=1 of the recurrence shown in the Example 3.2 of "The Laurent phenomenon" (see Link lines, p. 10).

%H Seiichi Manyama, <a href="/A208213/b208213.txt">Table of n, a(n) for n = 0..9</a>

%H Sergey Fomin and Andrei Zelevinsky, <a href="http://arxiv.org/abs/math/0104241">The Laurent phenomenon</a>, arXiv:math/0104241v1 [math.CO] (2001), Advances in Applied Mathematics 28 (2002), 119-144.

%F From _Vaclav Kotesovec_, May 20 2015: (Start)

%F a(n) ~ c1^(d1^n) * c2^(d2^n) * c3^(d3^n), where

%F d1 = -0.834243184313921717115626125802356204078143759301838339196857934562...

%F d2 = 0.3433795689528896338577674315423659679880371604828202900379886914176...

%F d3 = 3.4908636153610320832578586942599902360901065988190180491588692431448...

%F are the roots of the equation d^3 + 1 = 3*d^2 + 2*d and

%F c1 = 0.8780803541847027315058502579763355822688533316057717751329965683549...

%F c2 = 0.4420233041946828357635108827822581168188691631054586381824944218534...

%F c3 = 1.0154140443448836210836588567949793209798883476847171784955774310427...

%F (End)

%p a:=proc(n) if n<3 then return 1: fi: return (a(n-1)^3*a(n-2)^2+1)/a(n-3): end: seq(a(i),i=0..10);

%t RecurrenceTable[{a[0]==a[1]==a[2]==1,a[n]==(a[n-1]^3 a[n-2]^2+1)/a[n-3]},a,{n,10}] (* _Harvey P. Dale_, Jan 24 2014 *)

%Y Cf. A005246, A208207, A208209, A208214.

%K nonn

%O 0,4

%A _Matthew C. Russell_, Apr 23 2012