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A141609 a(n)=(a(n - 1)*a(n - 2) + a(n - 1)^2)/a(n - 3). 0

%I

%S 1,1,1,2,6,48,1296,290304,1763596800,2400297571123200,

%T 19846204885558066176000000,

%U 223334408639880528216369404299444224000000,20780031060559302184531906881808103844643569442380668928000000000000

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

%C A sequence constructed to have the pattern of a Somos-type sequence, but dominated by the Somos-4 sequence A006720.

%F a(n+1) / a(n) = A006277(n-1). - _Michael Somos_, Dec 29 2012

%t Clear[a, f, t, n, m] a[0] = 1; a[1] = 1; a[2] = 1; a[n_] := a[n] = (a[n - 1]*a[n - 2] + a[n - 1]^2)/a[n - 3]; Table[a[n], {n, 0, 20}]

%t RecurrenceTable[{a[1]==a[2]==a[3]==1,a[n]==(a[n-1]a[n-2]+a[n-1]^2)/a[n-3]}, a,{n,14}] (* _Harvey P. Dale_, Oct 01 2017 *)

%Y Cf. A006277, A006720, A006721, A006722.

%K nonn

%O 1,4

%A _Roger L. Bagula_, Aug 22 2008

%E Edited by _N. J. A. Sloane_, Aug 24 2008

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Last modified April 8 05:55 EDT 2020. Contains 333312 sequences. (Running on oeis4.)