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A208219 a(n)=(a(n-1)^3*a(n-3)+a(n-2))/a(n-4) with a(0)=a(1)=a(2)=a(3)=1. 2

%I #13 Mar 19 2017 10:38:56

%S 1,1,1,1,2,9,731,781235791,2145650135491172007486084385,

%T 802327342392981520933850619811649523436811893002103478524225246677189521545661182074

%N a(n)=(a(n-1)^3*a(n-3)+a(n-2))/a(n-4) with a(0)=a(1)=a(2)=a(3)=1.

%C This is the case a=1, b=1, c=3, y(0)=y(1)=y(2)=y(3)=1 of the recurrence shown in the Example 3.3 of "The Laurent phenomenon" (see Link lines, p. 10).

%C The next term (a(10)) has 258 digits. - _Harvey P. Dale_, Sep 21 2016

%H Seiichi Manyama, <a href="/A208219/b208219.txt">Table of n, a(n) for n = 0..11</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.

%p y:=proc(n) if n<4 then return 1: fi: return (y(n-1)^3*y(n-3)+y(n-2))/y(n-4): end:

%p seq(y(n),n=0..9);

%t RecurrenceTable[{a[0]==a[1]==a[2]==a[3]==1,a[n]==(a[n-1]^3 a[n-3]+ a[n-2])/ a[n-4]},a,{n,10}] (* _Harvey P. Dale_, Sep 21 2016 *)

%Y Cf. A048736, A208218, A208222.

%K nonn

%O 0,5

%A _Matthew C. Russell_, Apr 25 2012

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Last modified April 25 13:12 EDT 2024. Contains 371969 sequences. (Running on oeis4.)