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A208224 a(n)=(a(n-1)^2*a(n-3)^3+a(n-2))/a(n-4) with a(0)=a(1)=a(2)=a(3)=1. 4

%I #11 Mar 19 2017 10:39:19

%S 1,1,1,1,2,5,27,5837,2129410576,17850077316687753782569,

%T 2346851008195218976646246398770505953580095510848345967

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

%C This is the case a=3, b=1, c=2, 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(11)) has 133 digits. - _Harvey P. Dale_, Mar 06 2017

%H Seiichi Manyama, <a href="/A208224/b208224.txt">Table of n, a(n) for n = 0..13</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)^2*y(n-3)^3+y(n-2))/y(n-4): end:

%p seq(y(n),n=0..11);

%t RecurrenceTable[{a[0]==a[1]==a[2]==a[3]==1,a[n]==(a[n-1]^2*a[n-3]^3+ a[n-2])/ a[n-4]},a,{n,10}] (* _Harvey P. Dale_, Mar 06 2017 *)

%Y Cf. A048736, A208221, A208223, A208225, A208227.

%K nonn

%O 0,5

%A _Matthew C. Russell_, Apr 25 2012

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Last modified April 24 09:42 EDT 2024. Contains 371935 sequences. (Running on oeis4.)