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A141609 a(n)=(a(n - 1)*a(n - 2) + a(n - 1)^2)/a(n - 3). 0
1, 1, 1, 2, 6, 48, 1296, 290304, 1763596800, 2400297571123200, 19846204885558066176000000, 223334408639880528216369404299444224000000, 20780031060559302184531906881808103844643569442380668928000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

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

LINKS

Table of n, a(n) for n=1..13.

FORMULA

a(n+1) / a(n) = A006277(n-1). - Michael Somos, Dec 29 2012

MATHEMATICA

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}]

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 *)

CROSSREFS

Cf. A006277, A006720, A006721, A006722.

Sequence in context: A113296 A275462 A063744 * A096313 A230053 A245283

Adjacent sequences:  A141606 A141607 A141608 * A141610 A141611 A141612

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Aug 22 2008

EXTENSIONS

Edited by N. J. A. Sloane, Aug 24 2008

STATUS

approved

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Last modified February 27 07:07 EST 2020. Contains 332300 sequences. (Running on oeis4.)